When does a vitamin become a poison?

On the eve of autumn, many of us are buying vitamins and nutritional supplements in an effort to protect ourselves from seasonal illnesses.

However, often these seemingly useful drugs can carry a hidden danger, which manufacturers are in no hurry to inform you about. So, which of the most famous and frequently advertised dietary supplements and vitamins can harm your health? And how to recognize the first symptoms of an overdose in order to postpone the insidious bubble in time?

Ascorbic acid (vitamin C)

What is it. Available in the form of tablets for resorption or soluble "effervescent". Recommended for smokers, knowledge workers, people with weakened immune systems, pregnant women, children (for the prevention of colds, etc.), as well as those who experience severe and prolonged stress.

What's the catch. Our doctors are very fond of recommending "ascorbic acid" to everyone, right and left; and compassionate parents gladly feed their children with them, if they are afraid that "the child will get sick." And this is partly true: vitamin C really helps to fight infections, and in higher doses it is required by smokers, intellectuals, and just those who get tired a lot.

But! With a normal, regular diet, a modern person may well get vitamin C from food. It is found in high amounts in many fruits and vegetables, and even a serving of regular potatoes will provide you with a daily dose of about 100 mg. If you also actively take pill supplements, you can easily overdose, and its symptoms are nausea, vomiting, diarrhea, headache, insomnia, and hyperexcitability. And sometimes dysfunction of the kidneys and pancreas.

The above is a threat to someone who receives about 1 g of vitamin per day for a long time. But even with a less intense intake, there can also be unpleasant consequences. For example, ascorbic acid destroys tooth enamel and irritates the gastric mucosa, which means it is better to take it in the form of a drink - and even then, through a tube and after eating.


What is it. Food supplement, which is "extracted" from the shells of crabs and lobsters. It is used to prevent and relieve symptoms of arthritis, treat osteochondrosis and osteoarthritis.

What's the catch. Firstly, this drug should not be taken if you are allergic to fish and seafood, which many gullible consumers do not even suspect. Second, according to the International Arthritis Research Movement, glucosamine has pronounced side effects and causes gastrointestinal upset, diarrhea, constipation, headaches, skin rashes and itching. In addition, this dietary supplement helps to increase blood sugar levels, i.e. it is contraindicated for diabetics.

In turn, another organization - the British Medical Commission - recently issued a warning that glucosamine does not work well with the drug warfarin (which the manufacturers are silent about). Plus, it promotes fluid retention in tissues, leading to swelling and potentially damaging kidney and heart health.


What is it. This mineral is involved in the regulation of water balance in the body, a deficiency can lead to disruption of the heart, nerves and muscles. It is also important for maintaining joint and bone health, and potassium supplements are commonly used for arthritis and severe menopausal symptoms.

What's the catch. As always, it's all about the dose. Extreme hyperkalemia (high levels of potassium in the blood), as well as a deficiency, causes arrhythmias and cardiac arrest. Moreover, the less water in the body, the less potassium it needs for an overdose. There is a known case when, due to this property - and his own stupidity - a person was poisoned to death ... with bananas. The overly diligent bodybuilding fan spent 8 hours straight on the machines - which led to dehydration - and then decided to eat bananas - because they are high in carbohydrates necessary for muscle recovery. Only now, along with carbohydrates, bananas also contain a large amount of potassium - this killed the unlucky athlete.

If you are far from sports and fitness, you should not abuse potassium anyway. Dietary supplements with this mineral are contraindicated for people with high blood pressure, diseases of the cardiovascular system or kidneys, as well as for the elderly, because their body cannot cope with the excretion of potassium. The situation, frankly, is twofold: on the one hand, it must be taken during menopause and arthritis, and on the other, these problems usually arise in those who are over 55 and over.


What is it. Natural melatonin is a human hormone produced in the brain that is responsible for regulating sleep. In pill form, it is used to treat sleep disorders, in particular insomnia, as well as to prevent stress, infectious diseases and even cancer.

What's the catch. In theory, a lack of melatonin can actually provoke one of these problems. Actually, most of the unpleasant consequences of insomnia are due precisely to melatonin deficiency, since up to 70% of its production occurs during sleep.

However, all is well in moderation, and synthetic melatonin is produced in "excessive" dosages. One or two tablets (this is the usual recommended norm according to the instructions) can increase the content of this hormone in the blood by 20 times (!), And this is fraught with hypertension, migraines, a decrease in body temperature, weakness, depression, problems with potency and even infertility.

In general, the game is not worth the trouble - it's better to drink chamomile tea or take a simple hot bath. Moreover, the British Society of Pharmacists agreed with this: the organization stated that the effectiveness of melatonin in the treatment of insomnia looks extremely doubtful.


What is it. The most important mineral for the formation of bone tissue, necessary for the health of the skeleton, teeth, hair and nails. Also, without calcium, muscles and nerves cannot function normally, blood clotting does not occur, various hormones are not produced in sufficient quantities. Most often, calcium is prescribed for children and women, especially during menopause and pregnancy.

What's the catch. Recently, more and more sticks have been poured onto the unfortunate calcium. Recently, for example, a joint study by the universities of Auckland and Aberdeen showed that calcium intake increases the risk of cardiovascular disease and heart attacks in women. And even earlier, another study (conducted by specialists from Wake Forest University) linked the same calcium and containing it

foods with an increasing incidence of prostate cancer. Moreover, the higher the concentration of calcium in the blood of a man, the more chances that cancer will end fatally for him, scientists say.

Another trick of calcium is its ubiquitous "untwisted". Pharmaceutical manufacturers are actively promoting dietary supplements with this mineral, presenting it as a panacea - for women's health, beauty, skin, teeth, nails and everything in general. This is partly true, but many fanatical consumers are too addicted to "magic dietary supplements" and, without noticing it, get an overdose. Its mildest symptoms are muscle weakness, cramps, constipation, diarrhea, and increased thirst; in severe cases, fainting, dizziness and even anorexia begin, and since these manifestations are usually associated with a lack of any elements, and not with their excess, unsuspecting "patients" take dietary supplements even more actively.


What is it. The fastest growing seaweed rich in several minerals, especially iodine. Kelp supplements are usually advised for people with thyroid dysfunction.

What's the catch. No one undertakes to dispute the importance of iodine for the human body. Children and adolescents need it especially because deficiency can cause mental retardation, learning difficulties and other problems.

However, for adults with relatively good health and without pronounced problems with the thyroid gland, it is better not to get involved in dietary supplements with kelp. Several studies have shown that such drugs may not prevent, but, on the contrary, increase the risk of imbalance in hormones produced by the "thyroid", according to the Daily Mail. In addition, the components of kelp promote blood thickening, which means it is contraindicated for people with high blood pressure and heart disease.

Another, purely technical problem is related to the fact that the “harvest” of kelp is collected in rather polluted areas of the Pacific Ocean. A 2007 study by the University of California showed that 8 out of 9 popular kelp preparations contain arsenic and other toxic substances. And arsenic is, at a minimum, hair loss, headaches, loss of coordination, but in high doses - death.