Vitamins a Basic Overview
There's been a lot of controversy about vitamins in recent years – should we take them, should we not take them? Some nutritionists claim we can get all we need from the food we eat, others say the nutritional deficiencies in our modern-day diets mean some of us need a little helping hand from time to time. But whatever side of the fence you sit on, it's useful to know just exactly which vitamins might help improve your own individual health.
WHAT ARE THEY?
Vitamins are organic compounds we need to basically stay alive. Because the body does not produce enough of them itself, we get most of what we need from food. Every living thing on the planet needs vitamins in some shape or form. But what might be a vitamin to one species won't necessarily be to another. For example, C is a vitamin for humans but not for dogs.
Many people tend to worry about vitamin deficiency, but in fact, vitamins can be taken in excess too which can be dangerous.
FAT vs WATER
Vitamins are classified as either fat-soluble (A, D, E, and K) or water-soluble (B and C) which determines how they behave in the body. Once fat-soluble vitamins travel through the blood and reach tissues, they tend to stay there. So if you take too much of one of these vitamins they can prove harmful. Too much A, D,E or K can lead to a condition known as hypervitaminosis, the symptoms of which include nausea, drowsiness, hair loss and even permanent liver damage.
In contrast, water-soluble vitamins dissolve in H2O and aren't stored by the body. They are eliminated through urine which means we need a regular daily supply of them. It also means that an overdose is highly unlikely, but that still doesn't mean we should take huge amounts. All of the vitamins in the B group are water-soluble, which also means they can be destroyed by heat or water through cooking or by being exposed to the air. So we tend to lose many of these vitamins by the time the food in our fridges reaches our plates. The best way to retain as much Vitamin B and C as possible is to steam or grill foods, rather than boil them.
There are two types of vitamin A, preformed and pro. preformed – which comprises retinoic acid, retinal and retinol. It can be found in poultry, meats, fish and various dairy foods. It is the most active kind.
Provitamin A, which comes in the form of carotenoids, is contained in plant-based foods like fruit and vegetables, the most common and important of which is beta-carotene. This is an antioxidant used to decrease asthma symptoms brought on by exercise, prevent heart disease, treat AIDS, Alzheimer's, epilepsy and high blood pressure. So its medical benefits are many. Beta-carotene is also given to malnourished women to reduce their chances of death and night blindness during pregnancy. Some sun-sensitive people take beta-carotene supplements to reduce their risk of sunburn. In supplements, Vitamin A usually goes under the names of retinyl palmitate or retinyl acetate.
WHAT DOES IT DO?
Essential for good vision, especially in dim light, this powerful vitamin not only helps keep your eyes, teeth and skin healthy, it's also vital for your skeletal system and mucus membranes, which are the linings around some parts of the body, such as the nose.
Vitamin A also helps strengthen your immune system, enabling you to fight off nasty bugs much more easily. Until recently, it was believed that Vitamin A helped protect against lung cancer too, but studies now suggest it might actually increase the risk in smokers instead. The unique thing about this vitamin is that the body can make it's own from precursors found in green or orange fruits or vegetables called carotenes.
WHERE IS IT FOUND? One of the richest sources of vitamin A is any food that comes from an animal. Liver, egg yolks and seafood all have very high contents, as does cheese, fortified milk, kidney and cream. But it is best to get as much of your daily vitamin A from plants as all these foods are also high in saturated fat. Bright yellow and orange fruits such as grapefruit, apricots and cantaloupe, pack in this power vitamin, as do carrots, squash, sweet potatoes, pumpkin, spinach and broccoli.
HOW MUCH DO YOU NEED? If you don't get enough vitamin A, you can be prone to poor eyesight and more coughs and colds. Too much though and you could poison yourself or temporarily turn your skin yellow or orange. The recommended average daily amount for men is 0.7mg and for women, 0.6mg. The best way to get this is by eating a varied diet with plenty of fortified dairy, fruit and vegetables, beans and whole grains along with lean meats and oily fish.
Some research, however, suggests that having up to 1.5mg a day for a number of years might cause brittle bones, especially in older people. Postmenopausal women are at risk as well as men who've reached retirement age. This is because bone density naturally decreases with age.
For this reason, women who have gone through the menopause and men over 60, who are more at risk of osteoporosis, should avoid having liver or liver products like pâté, more than once a week, and should not take any supplements containing vitamin A (including fish liver oil) if they do eat such foods.
Many multivitamins contain vitamin A too, as well as a variety of other fish oils, so be mindful. If you do take supplements, make sure your daily intake from these and the foods rich in vitamin A combined does not exceed 1.5mg.
Other vitamins can also affect the absorption of vitamin A. For example, if you are lacking in vitamin D, you could suffer more from the damaging effects of too much vitamin A. People who tend to be at most risk of this are women who are pregnant or breastfeeding, those who don't expose themselves to much sun or cover up their skin for cultural reasons, people with darker coloured skin, and adults over the age of 65.
Generally, it is not advised that pregnant women take any multivitamins containing vitamin A unless they are advised to by a doctor.
Known as the sunshine vitamin because we rely on the sun's rays to produce it, D has many important functions. Not only can it protect against a host of diseases but it boosts mood and aids sleep too. It also helps to regulate the amount of calcium and phosphate in the body, which is vital to keep bones and teeth healthy. Vitamin D is important in several other ways as well. For example, muscles need it to move and nerves need it to carry messages between the brain and body parts. Plus the immune system uses it to fight off invading bacteria and viruses. This essential nutrient consists of a family of compounds - vitamins D1, D2, and D3. It can affect as many as 2,000 genes so is needed by almost every single cell you have. It isn’t found in many foods but is sometimes added to them. These products are usually labelled as ‘D-fortified.’ Vitamin D can also be taken as a dietary supplement in liquid or tablet form.
You actually get the majority of your vitamin D from sunlight on your skin. When UV-B rays hit, a reaction takes place that enables the skin cells to cleverly manufacture it. Because of skin cancer fears these days however, most of us don't get enough sun exposure. And those in hotter climates often wear sunscreen to protect themselves from burning. So it helps to supplement as much as you can with foods.
WHAT DOES IT DO? In addition to its primary benefits, research suggests that vitamin D might help reduce the risk of multiple sclerosis. In 2008 a US study also concluded that it could decrease the chances of developing heart disease.
This is the vitamin of the heart – namely because it helps prevent diseases that affect the organ, as well as the blood vessels running to and from it. But that’s not all it does. Vitamin E is also used to treat diseases of the brain and nervous system including Alzheimer’s and Parkinson’s. It can even be used to lessen the side effects of some drug treatments.
But vitamin E is not one substance alone, it is actually the collective name for a group of fat-soluble compounds that all have antioxidant activities. These are eight chemical forms broken down into two subtypes. The first four are alpha-, beta-, gamma-, and delta-tocopherol and the second four are alpha-, beta-, gamma-, and delta-tocotrienol. Alpha-tocopherol is the only form that is recognised as meeting human needs and so the one most commonly referred to as vitamin E.
When we eat, the liver absorbs vitamin E straight after the small intestine before secreting it back into the bloodstream. When the body breaks down food to use for energy, it also forms harmful free radicals called reactive oxygen species (ROS) and this vitamin prevents these from damaging cells. It also counteracts the damage caused by pollution, cigarette smoke, and UV rays from the sun.
WHAT DOES IT DO?
Aside from generally improving immune system function, vitamin E is also used in preventing cancer, especially lung and oral cancer in smokers. It also prevents polyps and gastric, pancreatic and prostate cancer. Not only does it benefit those with dementia and nervous system diseases, but it also eases symptoms of restless leg syndrome, cramps and epilepsy.
Pregnant women who suffer from high blood pressure often take vitamin E supplements to prevent dangerous complications like preeclampsia and it has been found to help ease the symptoms associated with premenstrual syndrome and hot flushes that accompany hormonal changes as well.
On top, this nutrient can be used to reduce the harmful effects of medical treatments like dialysis and radiotherapy and unwanted side effects like hair loss from drugs. Research has also found that there may be a relationship between vitamin E supplements and a reduced risk of cataract formation.
In one study, those who took supplements were found to have better lens clarity – a quality used to diagnose cataracts. Other benefits include improved physical endurance, increased energy, and improvement in muscle strength when taken before exercise because it aids cell membrane recovery from oxidative stress. As a cream, it can be applied to the skin to help prevent ageing, so is contained in many skin lotions.
Generally though, vitamin E works best as part of a team with other antioxidants like selenium and vitamin C so it is best taken in conjunction with other supplements.
Often labelled the 'forgotten vitamin', K is actually made up of a group of fat-soluble nutrients our bodies need to enable proteins to bind calcium in bones and other tissues and also help blood clot. In fact, without it, we would probably bleed to death.
There are three types of this vitamin. The first, K1, is used by the liver to coagulate blood and is found in plants and green leafy vegetables. The second, K2, goes to bones, blood vessels and other tissue and is created in the gastrointestinal tract and found in fermented foods. The third, K3, or menadione as it is also known, is synthetic, not natural, and not often used in economically developed countries due to its potential toxicity.
The best of the three is K2 as the healthiest way to increase your vitamin K levels is by eating more fermented foods like sauerkraut, cheese and certain meats, and also using what your body naturally makes.
According to experts, almost everyone is deficient in this important nutrient. While most of us do get just enough from the foods we eat to maintain healthy blood clotting, it isn't sufficient to protect us from certain illnesses and conditions, like pneumonia. Recent evidence also indicates that this vitamin is best absorbed together with vitamin D and neither works well without the other. Some dietary fat is also essential for it to be absorbed effectively.
WHAT DOES IT DO?
Firstly, vitamin K protects the heart by preventing the arteries from hardening and also helps ward off cardiovascular disease. But it is essential for strong, healthy bones too. Vitamin K2 is the most important nutrient for bone density and it can have a dramatic effect on people at risk of osteoporosis. In Japan, trials were shown to completely reverse the condition in those who already had it and there was an astonishing 80 per cent reduction in hip fractures among subjects and a 60 per cent reduction in vertebral fractures. Another study in the Netherlands showed it increased levels of osteocalcin, which controls the building of bone.
Research has also revealed that both K1 and K2 are effective in fighting off cancer. In a study published in the International Journal of Oncology in 2003, additional K2 was seen to slow down the growth of cancer cells in lung cancer patients. In 2008, a German research group discovered that vitamin K provided 50% more protection against prostate cancer. The vitamin also improves insulin sensitivity and those who get more of it are 20 per cent less likely to develop type 2 diabetes.
WHERE IS IT FOUND?
As mentioned, fermented foods like natto (a type of soybean) and certain cheeses are great sources of vitamin K and should be included in everyone's diet. But it is also contained in dark leafy vegetables like kale, brussels sprouts, asparagus, spring onions and dried basil. Among fruit, prunes have the highest content and foods specifically high in K2 include raw dairy products and meat from grass-fed animals, especially lamb or duck, dark poultry meat and beef liver.
HOW MUCH DO YOU NEED?
Adults need around 0.001mg per day of vitamin K per kilogram of their body weight. So someone who weighs 60kg would need 0.060mg daily and someone weighing 85kg would require 0.085mg. As is the case with other fat-soluble vitamins, because your body stores any leftover amounts in the liver for future use, you don't necessarily need it every day.
Not enough research has been carried out to show what the effects might be of taking regular high doses of vitamin K supplements but it is generally advised that those with heart trouble or people who have suffered a stroke or are prone to blood clotting shouldn't take supplements without seeking medical advice first. Pregnant or nursing women should also exercise caution. For most people though, taking 1mg or less of vitamin K supplements every day is unlikely to have any negative effects.
It is worth adding vitamin K supplements to your diet if you don't eat a lot of vegetables. Other conditions may also put you at higher risk of deficiency such as celiac disease, ulcerative colitis, Crohn's disease, and other illnesses that interfere with nutrient absorption. Taking drugs like antibiotics, cholesterol medication and aspirin may also reduce absorption.
Also known as Ascorbic acid or Dehydroascorbic acid, this is probably the most familiar of all of the nutrients. While most people would struggle to name a source of niacin or riboflavin, everyone can think of at least one food that contains vitamin C.
Often taken to ward off colds and flu, this vitamin is also needed for normal growth and repair of tissues in all parts of the body. Because we aren't able to make or store vitamin C ourselves, however, it is important that we include plenty of foods containing it, especially around winter months when there tends to be a lot of bugs circulating.
The vitamin is classified as an antioxidant, which means it helps keep chemical reactions in our bodies in check. Antioxidants also control the number of free radical molecules we have, which would otherwise cause damage to cells and tissue. Studies have shown that without adequate vitamin C, damage can be caused to the lenses of our eyes and even our DNA.
Another interesting feature about this nutrient and its antioxidant capabilities is that it changes the structure of the iron so it can be better absorbed. It is also needed to make collagen – the protein that helps keep our skin looking young and fresh by ‘holding’ it together. When we’re young, our skin stays smooth because it constantly regenerates itself. As we age, however, collagen production slows down, which causes it to sag and wrinkle. This is largely why there’s been a surge of beauty products containing vitamin C in recent years. Collagen is also the framework for our bones so without it, our skeletons would literally collapse!
WHAT DOES IT DO?
Apart from generally boosting the immune system, this mega vitamin also heals wounds and helps to form scar tissue, repairs teeth, bones and cartilage, and also forms a vital protein which is used to make blood vessels, ligaments, tendons and skin. Because, as an antioxidant, it battles free radicals, it also helps prevent arthritis, cancer and heart disease.
The most notable thing vitamin C is recognised for though is fighting the common cold. Research has demonstrated that people who take supplements or follow a vitamin c-rich diet get fewer colds and suffer for shorter amounts of time when do fall ill. It only helps though if it’s taken before symptoms kick in. Once a cold starts, additional amounts of the vitamin have little effect.
A report published in Seminars in Preventive and Alternative Medicine that looked at over 100 studies over a decade revealed a long list of benefits of vitamin C, including stress reduction and additional protection against immune system deficiencies, cardiovascular disease, prenatal health problems, and eye disease. One study in the American Journal of Clinical Nutrition found that those with the highest concentrations of vitamin C in their blood had a 42% lower risk of stroke too.
WHERE IS IT FOUND?
All food and vegetables contain some level of vitamin C, but those with the most include citrus fruits and juices, mango, kiwi fruit and cantaloupe, pineapple and berries. Guavas have a whopping 125mg per fruit, papaya contains 95mg and oranges 69mg. Vegetables with the highest amounts of vitamin C include Brussel sprouts, cauliflower, broccoli, spinach, cabbage, turnip and sweet and white potatoes. Two tomatoes pack in 56mg of the vitamin, kale 60mg per 50g, and a large yellow bell pepper has an impressive 100mg. Some packaged cereals and drinks have vitamin C added to them with the amount usually listed on the label.
But watch out for how you store and cook your food if you want to retain as much of this vitamin in it as possible – doing both for too long can deplete the amount drastically. Your body also stores less vitamin C if you smoke or drink a lot of alcohol.
HOW MUCH SHOULD I TAKE?
Because vitamin C is water-soluble, which means any excess amount is flushed out in urine, it is very rare for anyone to overdose on it. But it is recommended that people take no more than 2,000 mg per day to avoid getting an upset stomach. It is more worrying not to have enough of the vitamin as this can lead to anaemia, bleeding gums, decreased wound healing, nosebleeds, weight gain due to a slower metabolism, and painful joints. In its severest form, vitamin C deficiency can cause scurvy which makes you feel lethargic and causes muscle pain and a breakout of red dots on the skin.
The amount of vitamin C you need daily depends on your age. The recommended amounts are 75mg for male teens, 65mg for female teens, 90mg for male adults, 75mg for female adults, 85mg for pregnant women and 120mg for breastfeeding women.
THE B GROUP
B vitamins are a class of water-soluble nutrients that play an essential role in cell metabolism. Basically, they help the body get or create energy from the foods we eat by converting carbohydrates into glucose. They also help the body metabolize fats and protein. In addition, B vitamins are needed for healthy skin, hair, eyes, and liver and for the nervous system and brain to function properly. A lack of them can cause a range of illnesses and diseases including anaemia. They are often treated as a separate group of vitamins to the others because they are chemically distinct and can all exist together in the same foods. There are eight in total and each has a different name and role.
VITAMIN B1: THIAMINE
This was the first B vitamin to be discovered and is also known as the ‘anti-stress’ one because it strengthens the immune system and can improve our ability to withstand stressful conditions. Thiamine is found in both animals and plants and is needed for the body to make adenosine triphosphate (ATP), which is used by all cells for energy.
Because it can be found in many different foods, it’s rare for people to be deficient. However those with eating disorders, Crohn’s disease and alcoholics - who either don’t consume or absorb enough of the nutrient - are most likely to have inadequate amounts. They may suffer from depression, tiredness, irritability and abdominal pain as a result as they won’t properly digest carbohydrates.
Too little thiamine causes pyruvic acid to increase in the blood which can lead to a disease known as beriberi. Symptoms include difficulty breathing, confusion, a build-up of fluid in the lungs and uncontrollable eye movement. A more dangerous condition is the brain disorder Wernicke-Korsakoff syndrome, which is characterized by memory problems and nerve damage and is more common in alcoholics.
WHAT DOES IT DO?
Because it is needed by our bodies to use carbohydrates properly, thiamine is often used to help with digestive problems such as ulcerative colitis and diarrhoea. It boosts the immune system so is used in the treatment of AIDS, heart disease, canker sores, certain vision problems and diabetic pain. It has also been linked to the prevention of kidney disease in people with type 2 diabetes and cervical cancer.
Women take thiamine for nerve inflammation associated with pregnancy and it generally helps enhance memory, improve energy levels and fight stress as well. Alcoholics are given higher doses of the nutrient to cope with the side effects of withdrawal too.
Because insufficient levels of thiamine can cause dementia in the form of Wernicke-Korsakoff syndrome, some researchers believe it may help prevent Alzheimer’s. But not enough research has been done to confirm this. Small studies have suggested thiamine might ward off heart failure too as those with heart problems often take water pills to help the body flush out excess fluid, meaning the nutrient gets flushed out with it. But again, there is little concrete evidence.
WHERE IS IT FOUND?
Most foods contain some thiamine but the majority can be found in certain meats and organ meats like liver, kidney and heart. Pork, for example, has 1.12mg per 100g. Other good sources include legumes, rice, brewer’s yeast, wheat germ and enriched whole-grain and cereals. Trout has the highest content among fish with 0.23mg per 100g. Nuts and seeds can provide a healthy dose too. Sunflower seeds contain 1.48mg thiamine per 100g and macadamia nuts have 0.71mg. Edamame beans pack in 0.43mg per 100g.
In terms of additional supplementation, vitamin B1 is contained in virtually every multivitamin, including the chewable and liquid kinds. It is also sold as a supplement on its own in the form of soft gels, tablets, or lozenges. Other names for it include thiamine hydrochloride or thiamine mononitrate.
HOW MUCH DO I NEED?
The side effects of having too much thiamine are unknown, but research has shown that amounts exceeding the recommended daily dose can actually enhance brain functioning, and so have a positive, not negative effect.
Generally, however, it is recommended that children under the age of 12 should have no more than between 0.6 mg and 0.9mg per day. Teenagers should have around 1 to 1.2mg, men 1.2 mg and women 1.1 mg. Pregnant or breastfeeding women can have up to 1.4 mg daily. Doses for medical conditions like Wernicke-Korsakoff syndrome or beriberi should always be decided by a doctor and may be administered intravenously.
As a supplement, a daily dose of between 50 and 100 mg is usually safe. But because of the potential for side effects and interactions with certain medications, it is wise to seek medical advice first when considering taking a vitamin B1 supplement. Very high doses can cause stomach upset and it is better to take it as part of a vitamin B complex. Consuming too much of one kind of vitamin B over a long period of time may cause an imbalance in the other types.
The other name for this vitamin is riboflavin, and it is the only one among the group that can be visibly seen passing through the body. When we consume a lot of riboflavin in our diet, or in the form of a supplement, it actually turns urine bright yellow. The word riboflavin itself comes from the Latin word for the colour yellow, flavus.
Like all of the B vitamins, riboflavin is responsible for energy metabolism. Most of the healthiest foods around the world have high contents of the nutrient, like spinach and broccoli. It is important for the proper function of iron in the body too and without enough of it, we can’t make as many red blood cells as we need. This can eventually lead to anaemia.
Riboflavin is also required, among other nutrients, to recycle glutathione - one of the most important of all the antioxidants. It is used in baby foods, fruit drinks, breakfast cereals, pastas, and processed cheese, as well as vitamin-enriched milk products, and some energy drinks. But generally, it’s hard to put riboflavin into liquid products because it doesn’t have very good solubility in water.
When we don’t get enough vitamin B2, it can also be a sign of a general vitamin deficiency. There are two types of riboflavin deficiencies, primary and secondary. Primary is when a person isn’t getting enough of this specific nutrient through the foods they eat and secondary, when they aren’t absorbing enough for other reasons such as a pre-existing health condition. Symptoms of deficiency, known as ariboflavinosis, include cracked lips, dry skin, mouth ulcers, a sore throat, anaemia, tongue inflammation, and watery or bloodshot eyes.
WHAT DOES IT DO?
Riboflavin is essential in helping the body absorb other nutrients and maintaining healthy tissue. We also need it to help break down proteins, fats and carbohydrates, so it plays a vital role in supporting the body's energy supply.
Along with vitamin A, riboflavin helps maintain the mucous membranes in the digestive system, converts the amino acid tryptophan, which supports growth, into niacin (vitamin B3) boosts hormone production, helps keep eyes, nerves and muscles in good condition and also aids with the proper development of a foetus in the womb.
WHERE IS IT FOUND?
In a standard Western diet, we receive about a quarter to a third of our daily vitamin B2 from milk and various other dairy products. In fact, milk and yoghurt are probably the best and easiest sources of riboflavin.
But certain mushrooms are an excellent alternative and many leafy green vegetables are packed full of riboflavin. Among the non-dairy animal foods, turkey, sardines, and eggs contain the highest amounts and soy foods are rich in it as well.
Aside from broccoli, vegetables including cauliflower, Brussels sprouts, peppers, root vegetables, and squash also contain a lot of riboflavin. And it can be found in some natural sweeteners such as maple syrup, which contains about 6% of the recommended daily allowance. Yeast extract is considered to be exceptionally rich in vitamin B2, which is why many cereals contain it.
Riboflavin is destroyed by light however, so food should be stored away from bright sunlight to retain its levels. And while it is not affected by heat, the nutrient can be lost in water when foods are boiled or soaked. So roasting and steaming instead of frying or scalding are the best ways to preserve amounts.
HOW MUCH DO YOU NEED?
Most healthy people who eat a well-balanced diet get enough riboflavin. But elderly people and alcoholics may be at risk of deficiency due to a lack of healthy foods. Babies need around 0.3-0.4mg per day while children aged one to three need 0.5mg. Between the ages of four to eight, 0.6mg is advised and in teenage years around 1mg for girls and 1.3mg for boys. Men aged 19 years or older should stick to 1.3mg per day and women, 1.1mg. When pregnant, they should increase this amount to 1.4mg.
Riboflavin as a supplement is best absorbed when it’s taken between meals. Although it is generally considered safe, even at high doses, taking above 10mg per day can cause eye damage from the sun, so people who take extra should wear sunglasses with UV protection. Too much riboflavin can also cause a burning sensation on the skin or itching.
Otherwise known as niacin, the third B in the group is required for regulating blood sugar as well as processing fat in the body and lowering cholesterol levels. Without enough niacin, we can develop a condition called pellagra, which causes a range of symptoms including dermatitis, inflammation inside the mouth, diarrhoea, dementia, amnesia and even death. Just a small deficiency in this nutrient can lead to anxiety, fatigue, poor concentration and depression, so niacin is very important. Because it is water-soluble and well regulated by the body, an overdose is highly unlikely unless niacin is taken in supplement form.
A lack of niacin can also be observed in pandemic deficiency disease, which is caused by not having enough of five crucial vitamins - niacin, vitamin C, thiamin, vitamin D, and vitamin A. This condition is usually found in areas where there is a lot of poverty and malnutrition.
Although niacin has not been found to help reduce the risk of cardiovascular disease in people already on statin drugs for high cholesterol, it has had positive effects on those not taking medication.
WHAT DOES IT DO?
The most vital role niacin plays in our health is in helping to reduce cholesterol levels. Numerous studies have shown that the nutrient can boost amounts of good HDL cholesterol while lowering triglycerides (a type of fat found in the blood) as good as or even better than some prescription drugs. It also lowers the amount of bad LDL cholesterol that can block arteries.
But niacin is only effective as a cholesterol-reducing treatment when given in fairly high doses. These amounts can cause other health problems such as glucose intolerance or liver damage so must be prescribed by a doctor. It’s never a good idea to treat yourself with shop-bought supplements.
Niacin has other health benefits for the heart too such as reducing hardening of the arteries – in people who have already had a heart attack, the nutrient lowers the chances of them having another. Research has also shown that it may help lower the risk of osteoarthritis, type 1 diabetes and cataracts. niacin keeps your skin cells healthy, regulates numerous enzymes and allows nerves to function properly
WHERE CAN YOU FIND IT?
Most vegetables contain varying amounts of niacin but seaweed is the best non-meat source along with avocado and green peas, which contain over 1.5mg per 100g. Potatoes, butternut squash, corn, parsnip, and pumpkins all provide between 1 and 4mg each. Vegetables that contain just under 1mg per serving include asparagus, Brussels sprouts, French beans, onions and summer squash. However, fortified grains, which provide up to 27mg per serving, and meats, which have around 5 to 7mg, serve as better dietary sources. Cooked lamb’s liver contains 16.7mg per 100g, cooked chicken breast has 14.8mg per 100g and among fish, Yellowfin tuna has the most with 22.1mg per 100g.
HOW MUCH SHOULD YOU TAKE?
Everyone needs a certain amount of niacin - from food or supplements - for their bodies to function normally. But take too much or you might run into problems. Adults generally should never have more than 35 milligrams per day, except under a doctor's supervision. The actual recommended daily amounts are 16mg for adult males and 14mg for adult females, increasing to 18mg for pregnant women. Children should have no more than between 2-16mg, depending on their age.
Since niacin can upset your stomach, it is better tolerated as a supplement when taken with food. Other side effects of taking too much include jaundice and blurred vision, along with what’s known as the niacin ‘flush’ – a heat flush throughout the body. This reaction happens because the vitamin contains a natural property that automatically dilates blood vessels. The skin turns blotchy red and may feel very hot to touch. In addition to suddenly being uncomfortably hot, you might also experience severe itching coupled with a rash. Niacin flushes usually pass after half an hour though and leave no lasting negative effects. A much more serious yet rare side effect of overdosing is a sudden drop in blood pressure, which can cause long term damage to vital organs.
Found in a variety of plants and animals, pantothenic acid is often included along with other B vitamins as part of complex formulas in supplements and fortified food and drink products. It has several uses but is mostly taken to treat dietary deficiencies, baldness, asthma, attention deficit-hyperactivity disorder, yeast infections and respiratory disorders. It is important to have enough so our bodies can properly use carbohydrates, proteins, and fats and it also promotes healthy skin. Without it, we would be unable to make hormones and our immune systems would literally collapse!
The type that's usually used in multivitamin supplements is a form of the nutrient called pantothenol which is a more stable kind. Another supplemental form of pantothenic acid is calcium pantothenate, a salt which is often used in dietary supplements because it is easier to digest and can improve oxygen utilisation in athletes as well as reduce the amount of lactic acid they produce when training. Lactic acid is the chemical that results in the burning sensation often felt during intense exercise.
The name pantothenic acid was taken from the Greek word pantothen, meaning 'on all sides' or 'from all quarters'. It is among the most important of the B vitamins for the basic processes of life. Luckily, it is also the nutrient we are least likely to suffer a deficiency in. This is because it's commonly found in so many different foods. One of the foods that doesn't contain it however is olive oil. Although olives themselves have small amounts, once pressed, this content is lost because olive oil is 100 per cent fat and pantothenic acid is water-soluble.
WHAT DOES IT DO?
The most vital role of pantothenic acid in terms of health support is its involvement in the production of a molecule called Coenzyme A (CoA). CoA is one of the most important chemicals needed to sustain life. In fact, some scientists suggest that the origin of life itself can be traced back to this one chemical. It is what allows carbohydrates, fats, and proteins to be used by the body as fuel sources. And we would die if this didn't happen.
Pantothenic acid is also necessary to support fats for storage, which then act as a building block for key hormones to guide metabolic processes. Although it might sound like this prompts weight gain, there is no evidence to show that blocking pantothenic acid activity in any way aids weight loss. Plus it may not be healthy for the body so it is not advisable.
Some studies have also shown that applying pantothenic acid ointment directly to the skin can shorten the healing time of wounds and reduce scar tissue as well as help reduce acne. Pantethine, another derivative of pantothenic acid, may have a cholesterol-lowering effect in humans too.
WHERE CAN YOU FIND IT?
It's probably easier to look at which foods don't contain pantothenic acid than which do. The highest content can be found in vegetables but even herbs and spices have measurable amounts. Root vegetables like sweet potatoes, leafy vegetables such as turnip greens, stems including asparagus, and also mushrooms are all full of the nutrient. Fish, animal meats, fruit, legumes, grains, eggs, and dairy foods contain it too. So there are a wide diversity of foods groups covered. Cooked shiitake mushrooms pack in 3.59mg of pantothenic acid per 100g, Gjetost cheese (made from a mixture of goat and cow's milk) has 3.35mg per 100g, cooked trout 2.24mg per 100g, avocados 1.46mg per 100g and there's 1.65mg in 100g of cooked lean pork.
HOW MUCH DO YOU NEED?
The recommended daily intake of pantothenic acid is around 5mg for both men and women. In pregnant women, this amount is slightly higher at 6mg, and in breastfeeding women, 7mg. Infants under the age of six months should have no more than 1.7mg daily and those aged six months to a year, 1.8mg. Between the ages of one and three it's 2mg and from four until teenage year the amount varies from 3mg to 4mg. There is no known toxicity level for pantothenic acid in humans, but doses of up to 1,200mg can cause gastrointestinal side effects including heartburn and nausea.
The superstar of the B group, this nutrient supports more functions than any of the other vitamins. Not only does it enable our bodies to metabolize amino acids - which are the building blocks of cells, muscle and tissue - without pyridoxine various chemicals we need wouldn’t be produced either. Among these are the feel-good chemical serotonin and norepinephrine, which both balance out mood, dopamine, which is a neurotransmitter that helps control the brain’s reward and pleasure centres, and adrenaline, a hormone released from the adrenal glands that prepares the body for fight or flight.
Also, when it’s taken together with vitamins B9 and B12, pyridoxine helps reduce the levels of another amino acid called homocysteine in the blood, which is increasingly being recognised as a risk factor for disease and is seen as a predictor of potential health problems such as cardiovascular disease, Alzheimer’s, and stroke.
WHAT DOES IT DO?
Pyridoxine helps red blood cells form and regenerate. It also helps our bodies make DNA and RNA molecules which are the bodies ‘coders’. Some research also shows it may help combat male infertility, pernicious anaemia (where your immune system attacks healthy cells in your stomach hindering the production of healthy red blood cells) osteoarthritis, bursitis, and chronic fatigue syndrome, among several other conditions.
On the neurological side, it’s been shown to improve memory, prevent depression and tackle sleep disorders. The benefits may include positive effects on conditions such as chronic pain, seizures, chronic pain, and Parkinson’s disease too. Researchers think this might be linked to the fact that the nutrient plays a vital role in the production of serotonin and dopamine, which are needed for nerve communication.
People who don’t get enough vitamin B6 may have an increased risk of heart disease and rheumatoid arthritis. In one large-scale study in Japan, researchers discovered that those who consumed a lot of foods containing both vitamin B6 and B12 had a reduced chance of suffering heart failure and stroke. In a Duke University Medical Centre review of studies on nutritional supplements, researchers found that vitamin B6 could be effective in reducing the risk of macular degeneration (a cause of blindness) as well.
WHERE IS IT FOUND?
Vitamin B6 is found in a wide variety of foods such as pork, poultry, fish, bread, oatmeal, wheat germ and rice. Nuts and seeds are excellent providers too. Sunflower seeds come high on the list with 1.35mg per 100g. Sesame seeds, flaxseeds and pumpkin and squash seeds are also rich in pyridoxine as are pistachio nuts which contain 1.12mg per 100g. Cooked tuna has 1.04mg per 100g and turkey and chicken contain around 0.81mg per 100g. Other good B6 foods are eggs, soya beans, potatoes and peanuts It is important to get enough pyridoxine in our diets as, over time, a deficiency can lead to skin inflammation, confusion, depression, convulsions, and low levels of iron.
HOW MUCH SHOULD I TAKE?
People need sources of vitamin B6 as well as the other B vitamins every day, but the exact amount of pyridoxine required depends on various factors like age, gender, and any special circumstances, such as whether the individual is pregnant or breastfeeding or has an illness.
Babies up to the age of six months require 0.1mg per day, infants aged seven months to a year 0.3 mg, children aged one to three years 0.5 mg, from four to eight years, 0.6mg daily, and from nine up to teenage years, 1mg. Between the ages of 14 to 18 males require 1.3mg and females 1.2mg.
Among adults, men and women aged 19 to 50 are advised to have 1.3mg per day. After the age of 51 men should increase this amount to 1.7mg and women to 1.5mg.
Most people who eat a well-balanced, carried diet will all the vitamin B6 they need without having to take dietary supplements. For older adults, however, getting a sufficient dose can be difficult if they live alone and cook less. So elderly people should ask about having their pyridoxine levels tested by their doctor.
Some people may actually be getting too much of the nutrient if they consume a lot of energy drinks. Although the vitamin is water-soluble, meaning any excess will be excreted, too much can be hard on the kidneys as they have to work overtime to get rid of it. High amounts of vitamin B6 may increase the risk of health problems such as nausea, abdominal pain, and even neurological disorders.
Taking more than 200mg a day of vitamin B6 for a long time can lead to a condition known as peripheral neuropathy, which is a loss of feeling in the arms and legs. Generally, the symptoms are reversible though, so should go away once the amount is reduced.
B7 Biotin is a coenzyme and also known as vitamin H. It plays a key role in the body by supporting the metabolism and digestive tract as well as the health of the skin and nerves. Biotin supplements have been looked at as a potential treatment for several health conditions, including type 2 diabetes. Research has shown that it can decrease insulin resistance and nerve symptoms related to the illness and when taken together with chromium, can help regulate blood sugar levels. Studies have also shown that biotin helps strengthen brittle nails and reduces hair loss as well as improving symptoms of depression. And back in the 1940s, a researcher demonstrated that adding high biotin foods to the diet of a lactating mothers reduced symptoms of cradle cap in the infants they were nursing.
WHAT DOES IT DO?
Biotin can aid weight loss because it affects blood sugar levels. But it has many other health benefits too, such as tissue maintenance, promoting healthy skin, providing relief from heart problems, as well as helping with the symptoms of Parkinson’s disease, Rett syndrome and vaginal candidiasis. Not getting enough biotin is also known to cause a skin rash. This is because the nutrient is necessary for building good fats in the skin to keep it supple and moist. When these fats aren’t present, the skin becomes flaky and irritated. As it helps regulate the metabolism, a lack of biotin can also lead to fatigue, depression, pain in the muscles, low mood and anaemia. Other indicating symptoms of a deficiency include a loss of appetite and a dry scalp or dandruff. The most serious symptoms are neurological disorders and restricted growth in infants.
WHERE IS IT FOUND?
Nuts, root vegetables, and eggs are among the best sources of biotin as they each contain more than a quarter of our daily requirements in just one serving. Tofu, mushrooms, and various seeds can be rich in the nutrient too, with around 10% of our daily requirement packed into a portion.
Consuming foods like egg yolks, milk, liver, kidney and fish will make sure we get enough, but it is worth noting that raw egg whites restrict the absorption of biotin because they contain a compound called avidin that binds with it, so they should be avoided in large quantities. For vegetarians, non-meat sources include unpolished rice, soybeans, oats, potatoes, nuts, broccoli, spinach, cauliflower and bananas. The majority of natural foods retain most of their biotin even after cooking. But this isn’t the case for tinned foods, which lose between 40-60% of their levels.
HOW MUCH DO YOU NEED?
Most of us don't need biotin supplements, not only because we get all we require from the food we consume but because our bodies also recycle the biotin we've already used. This means a genuine deficiency is uncommon. Plus, the average adult eats about double their daily requirement anyway. It is generally recommended that babies up to the age of six months have 5mcg of biotin daily, aged between six months and one they should have 6mcg, and between one to three years of age, this increases to 8mcg. From four to 13 years the amount is between 12 to 20mcg and teenagers are advised to have 25mcg. Adults both male and female need 30mcg per day but lactating women should increase this amount to 35mcg.
Although biotin deficiency is rare, it can occur in people who drink a lot of alcohol or consume a lot of foods that contain raw egg white. Those who suffer from a genetic disorder called infant seborrheic dermatitis will also have trouble retaining sufficient amounts as well as people who have had to have their stomachs removed for medical reasons. Supplements must be taken with care however, as in some people, they can result in skin conditions like acne. There are concerns that an excess can have a negative effect on the kidneys too, so it is wise for those with kidney problems to seek medical advice first.
While folic acid and folate are often marketed as the same thing, their metabolic effects can be quite different. Folate is the bioavailable, natural form of vitamin B9 found in various plant and animal foods. Folic acid, on the other hand, is the synthetic form of the vitamin, often found in supplements and fortified foods. The body prefers using folate and regulates healthy levels by releasing any excess through the urine.
Folic acid is most often associated with pregnancy because it is essential for the healthy development of babies. When women are trying to conceive or are already pregnant, it is the supplement they are most often advised to take. This is because folic acid is needed to support the formation of a baby’s spinal cord and brain, which begin developing almost straight away.
Having enough folic acid in the blood in the early stages of pregnancy can actually prevent serious neural tube defects, such spina bifida, which occurs when one or more bones in the spine don’t form properly. It’s hard for a woman to take in enough of this nutrient through food alone though, so supplementation is essential. Storing food for too long or overcooking it can also reduce the amount of folate, the natural form of folic acid, in food.
WHAT DOES IT DO?
As well as supporting a healthy pregnancy, folic acid is used to prevent and treat anaemia (low iron levels in the blood) and for other conditions commonly associated with folate deficiency, including liver disease, ulcerative colitis, and kidney malfunction. It also helps the bowel absorb nutrients properly. Some people use the nutrient to prevent cervical or colon cancers, heart disease and stroke, as well as to reduce levels of a chemical called homocysteine. When people have too much of this chemical in the blood it can lead to heart disease.
Other ways in which folic acid can benefit health is in the treatment of age-related hearing loss, memory loss, and Alzheimer’s. It helps to prevent the eye disease macular degeneration, weak bones, restless leg syndrome, nerve pain, and insomnia as well. It is also used to reduce the harmful side effects of treatment with medications lometrexol and methotrexate. Some people apply folic acid directly to gums for treating ulcers and mouth infections.
WHERE IS IT FOUND?
Over the last two decades, folic acid has been added to many foods including breads, cereals, pasta, bakery items, cookies, and crackers. Foods that are naturally high in folate include broccoli, lettuce, spinach, okra, and asparagus. Some fruits contain high amounts, including bananas, melons, and lemons. Beans, yeast, mushrooms, beef, liver and kidney meats, tomato juice and orange juice are also good sources.
Beans and peas especially high in folic acid include lima beans, greens and black-eyed peas, pinto beans, and kidney beans. A small bowl of any type of lentils will provide most of the recommended daily amount of folate. Avocado, holds up to 90mcg folate per portion, which accounts for around 22% of our daily needs. While Brussels sprouts probably aren’t most people’s favourite vegetable, they are one of the best foods for this nutrient - one serving provides approximately 25% of the daily recommended amount for adults.
HOW MUCH SHOULD I TAKE?
Babies up to the age of six months need 65 mcg per day and those aged six months to one require 85 mcg per day. From one to three, they should have 150 mcg daily and children aged four to eight need 200 mcg per day. Between nine and 13 the recommended amount is 300 mcg daily and teenagers and adults should have 400 mcg daily. Pregnant women need much more though and should increase the amount to 600 mcg per day and 500 mcg when breastfeeding. Folic acid needs increase when people are under physiological stress, drink a lot of alcohol, have high metabolisms or suffer from an overactive thyroid.
While it isn’t dangerous to consume too much folate, an excess of folic acid in fortified foods and supplements can be toxic. Folate deficiency is almost impossible to tell apart from vitamin B12 deficiency, but if large doses of folic acid are given to someone who isn’t actually deficient in folate, it can cause irreversible neurological damage.
Having too much folic acid in the body can also cause digestive problems, loss of appetite, bloating and nausea, excessive excitement, irritability and zinc deficiency. More severe side effects include psychotic behaviour, trouble concentrating, confusion, and even seizures. An allergic reaction to folic acid may cause wheezing and swelling of the face and throat.
The last in the group of B vitamins, B12 is the largest and most complex vitamin of them all. It also plays a key role in aiding the normal functioning of the brain and nervous system. It is needed for the formation of blood and is involved in the metabolism of all cells, especially those affecting DNA regulation and synthesis as well as fatty acids and amino acids. No living creature or plant is capable of producing cobalamin, but microorganisms are as they contain the necessary enzymes. As these are found in animals and dairy products, many foods are still a primary, sound source of the nutrient.
Two steps are required for the body to absorb cobalamin from food. First, hydrochloric acid in the stomach separates it from the protein to which it is attached. It is then mixed up with a protein produced in the stomach called intrinsic factor and absorbed by the body. Some people have a medical condition which means their bodies don’t produce intrinsic factor though and so have trouble getting enough vitamin B12 from foods and dietary supplements.
WHAT DOES IT DO?
Cobalamin has many benefits such as reducing tiredness, keeping the immune system working properly, contributing to normal cell division, aiding the formation of red blood cells, and supporting natural energy production. It has been looked at as a treatment for many conditions including breast cancer, heart disease, high cholesterol and sickle cell disease. Studies suggest that it does not help with stroke risk or lung cancer, however.
Low levels of cobalamin are more common in people over the age of 50 or those with digestive problems and certain types of anaemia. But any reduction can be felt. Even temporary low levels of the nutrient can cause fatigue, memory loss, weakness, and other problems relating to the nervous system. One study showed that cobalamin supplements used with folic acid and vitamin B6, reduced the risks of the eye condition macular degeneration (AMD) in older women with heart disease or with multiple risk factors for heart disease.
WHERE IS IT FOUND?
Because the nutrient is found mostly in meat, fish and dairy, vegans and vegetarians are more susceptible to a deficiency. One of the best food sources to help fulfil daily requirements is clams. Just three ounces of these molluscs boast 84.1 μg of cobalamin. Beef is another good source and three ounces has 70.7 μg cobalamin. The amount is higher if the meat comes from grass-fed cattle. Oysters are another mollusc that contain a plentiful supply - six medium oysters have 16.4 μg of the nutrient. Then comes chicken, turkey, salmon, trout, and fortified soy and cereal products.
HOW MUCH DO YOU NEED?
Vitamin B12 can be consumed in large doses because any leftover amount is excreted by the body or stored in the liver for use when supplies run low. Amazingly, stores of B12 can actually last in the body for up to a year. The recommended dietary allowance, which includes the vitamin B-12 you get from both food and any supplements, is 0.4mcg per day for babies up to the age of six months, then 0.5mcg up to the age of one. Between the ages of one and three, the amount is 0.9mcg per day and four to eight years it’s 1.2mcg, increasing to 1.8mcg per day in the nine to 13 age group. Teenagers and adults of both sexes are advised to have 2.4mcg daily, and pregnant women, 2.6mcg.
Even at high doses, cobalamin is fairly safe. While there aren't very many side effects relating to consuming too much of it to be worried about, in rare cases, excess supplementation may cause numbness or tingling in the arms, hands and face. People with Leber's Disease are especially warned not to take vitamin B12 supplements because they can cause damage to the optic nerve. People with a history of gout should be careful as the vitamin can trigger the condition in people who are susceptible. There is also a link between very high doses of cobalamin and certain cancers. One study showed that the risk of developing prostate cancer could triple. Less serious side effects include nausea, diarrhoea, and difficulty swallowing.