How well are food supplements safe and do they really work?

The story of Jim McCants, a man who eventually needed a liver transplant after consuming green tea capsules raised new questions about dietary supplements.

What are your risks and health benefits?

When Jim McCants started taking green tea tablets, he thought it would be good for his health.

Instead, the compounds apparently caused severe liver damage and required an emergency transplant.

Experts say this type of experience, like that of McCants, is "extremely unusual".

In the UK, supplements are subject to safety regulations and health claims manufacturers of these products.

Approved supplements sold in respected companies are almost always safe, as long as the manufacturers' instructions are followed, say the doctors.

But we should not assume that dietary supplements do not have the potential to cause harm, says Dr. Wayne Carter, University of Nottingham, England.

If you take supplements in amounts above recommended levels, there will be risks.

Although in many cases, the excess of a supplement can be excreted, it is possible that it is toxic, especially to the liver, the organ responsible for it. eliminating the toxicity of the substances we consume.

"I think sometimes the idea that people are getting is" it's good for me, so if I take it more, it'll be even better, "says Dr. Carter.

"This has its risks."

There is also the potential risk of taking multiple medications at the same time, without distinction, said Dr. Carter.

Sometimes these can interact with each other, so that one supplement can enhance the effects of another, and in other cases, they may contain one or more nutrients of the same type, possibly leading to excessive levels.

Some of us may be less able to metabolize certain substances effectively, which may also affect how they affect us.

"The warning with the consumption of a supplement is that this can be safe in a large population, but not in all", adds the expert.

But if these are the potential risks, what are the health benefits?

For kids

There are some supplements widely recognized by experts that may be of benefit to the public.

The United Kingdom's Health Services (NHS) recommends that women who are planning to have a baby and pregnant women take a folic acid supplement until 12 weeks of pregnancy. to avoid common congenital abnormalities in babies.

Vitamin D supplements are also recommended for babies, children ages 1 to 4 and those who are not exposed to the sun.

The rest of the population is advised to consider consuming a vitamin D supplement.

The lack of vitamin D, which we get mainly from the sun, can lead to bone deformities, such as rickets in children, and bone pain caused by a disorder called osteomalacia in adults.

Dr. Benjamin Jacobs, pediatric specialist at the Roya National Orthopedic Hospital, said: "100 years ago, most London children suffered from rickets, which was virtually abolished with the practice of giving children a vitamin supplement. "

A vitamin K injection is also usually given to babies during the first 24 hours of their life to avoid a rare but serious blood disease.

Science in evolution

Dr. Jacobs states that supplements are also important for people with restricted diets or allergies.

Experts say that vegans might need a vitamin B12 supplement because it is found naturally in foods of animal origin.

However, with many other supplements the evidence is less clear there is a benefit for most people.

According to the NHS, most people do not need to take any other vitamin supplements and can get all the vitamins and minerals they need, with the exception of vitamin D , with a balanced diet.

The benefits of fish oil pills, a supplement linked to a wide variety of presumed benefits, ranging from improving cardiovascular health to increasing brain function, are only not conclusive.

A recent study of clinical trials found that the evidence that fish oil pills protect the heart is questionable.

Sam Jennings, director of Berry Ottaway & Associates Ltd, a consulting company that works with supplement manufacturers, says nutrition is essential. "a science in constant evolution, new data is still emerging. "

He adds: "What has been clarified is that, with the supplements, the benefits will not always be obvious to everyone, because that will depend on the individual's own training and the benefits that can be obtained when the consumption." an extra nutrient of some kind. "

Dr. Carter says that, according to him, before taking a supplement, people see the type of scientific evidence to support their supposed benefits and verify the presence of warnings about the compound.

Tips for taking supplements

• Buy them from respectable suppliers because they must have passed strict security safeguards.
• Check if they have been tested in clinical trials with a population similar to yours (similar age, gender, etc.).
• Check the warnings. For example, people with heart problems should check if the supplement is not toxic to the heart.
• Be careful when taking multiple supplements at the same time.
• Take only the recommended doses.

Source: Dr. .Wayne Carter, University of Nottingham.

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