Dietary supplements are a $30 billion racket
What experts actually recommend
Let's separate the nutrients from illusions and deadly deceptions
Translated by Vyacheslav Golovanov, GeekTimes
More than 90,000 vitamins and dietary supplements are sold in the USA. They are available in the form of tablets, powders, drinks and bars. They all promise us improved versions of themselves–stronger bones, a slimmer waist, healthier muscles, a happier gut, improved sex life and brain function. They predict the departure from diseases and from aging.
And in general, we believe them. The volume of the dietary supplement industry in the United States is estimated at $ 30 billion. Recent studies show that 52% of Americans take at least one dietary supplement, and 10% take four or more types of them. But do we need it? Are we really getting healthier, smarter, stronger, better thanks to these daily doses?
The answer is probably no. Most dietary supplements have little or no data proving their effectiveness, not to mention safety. They are often promoted on the basis of scant studies conducted on rodents and in Petri dishes or on small samples of people. The industry is full of hype and wishful thinking – even the evidence for the usefulness of multivitamins is not particularly convincing. And there are generally deadly deceptions. In addition, almost no one follows the industry.
The Food and Drug Administration (Eng. The Food and Drug Administration (FDA) does not have the authority to investigate dietary supplements for safety and efficacy before they enter the market. This means that the contents of bottles and jars lining up on the shelves of grocery stores, pharmacies and special shops may not even correspond to the declared composition. They can be radically different from party to party. They may contain hidden, prohibited ingredients, for example, amphetamines. Or even harmful toxins like lead and cadmium.
And even after these potentially dangerous drugs enter the market, the FDA does not have enough opportunities to keep up with all the products and statements about their action, and throw out unscrupulous market participants. And it's hard to blame them. Doctors also do not have time for 90,000 products.
Two experts from Harvard decided to help this trouble and compiled a small guide to effective dietary supplements. Preventive medicine experts Joanne Manson and Shari Bassuk described which dietary supplements are effective and when. This list is quite short. That's what they and other experts recommend, along with a quick course on navigating the world of dietary supplements.
What to take
Firstly, the couple emphasizes, the best way to get vitamins and minerals is to stick to a healthy diet. Trace elements are often better absorbed by the body when they come with food, and there they are presented in optimal proportions compared to a bunch of concentrated substances in a tablet.
For the health of adults and the elderly
Vitamin B12 – if you are over 50. At this age, the body may no longer be able to cope with the processing of the protein-related form of vitamin B12. Dietary supplements can help make up for the deficiency up to the recommended daily dose of 2.4 mcg per day.
Vitamin D – As we age, our skin and kidneys produce and process vitamin D less efficiently, respectively. For some people, supplemental vitamin D can help get to the recommended daily dose of 600 IU (international units) for adults up to 70 years old and 800 IU for older people. Some health organizations recommend higher doses, up to 2000 IU per day – but this is a controversial issue. If the vitamin D content in the blood is exceeded, it can become toxic, cause nausea, weakness and constipation.
Calcium is possible. Calcium absorption worsens with age. Today, the recommended daily doses of calcium are as follows: 1000 mg for men from 51 to 70, 1200 mg for women from 51 to 70 and for all adults over 70 years old. A recent analysis suggests that moderate doses (up to 1000 mg per day) can reduce the risk of bone fractures and bone loss in men and women after menopause at the age of 65. But excess calcium can also cause constipation. Excess calcium obtained from dietary supplements can increase the risk of kidney stones.
In general, multivitamins are not recommended for healthy people. There is no indisputable evidence of their benefits. A 2013 analysis of 27 trials involving more than 400,000 people concluded that there was no clear evidence that multivitamins reduced the risks of cardiovascular disease, cancer, or mortality in general. A study that tracked the health of 6,000 men for 12 years found that they did not protect or improve cognitive abilities. One large randomized double-blind placebo study in the United States found that some people who took vitamins had a slight decrease in the risk of cancer (in particular, people with a diagnosed vitamin deficiency and previously diagnosed with cancer). But this study needs to be repeated with the involvement of women and with an increase in the reference data on nutrition.
For people with diseases
Various medications, dietary restrictions, and special conditions can affect the intake and assimilation of nutrients. For example, people who do not treat celiac disease may not receive enough iron, magnesium, zinc, B vitamins, vitamin D. Long-term use of proton pump inhibitors, for example, omeprazole, which inhibits gastric acid secretion, may disrupt the absorption of vitamin B12, calcium and magnesium. People taking metformin for the treatment of type II diabetes may have impaired absorption of vitamin B12, although the evidence for this is contradictory. Some patients with age-related macular degeneration may benefit from special supplements with vitamins C, E, beta–carotene, zinc and copper - according to one large-scale randomized study with a control group.
For pregnant women
There is obvious evidence, Manson and Basuk write, that women preparing for pregnancy and becoming pregnant should receive an adequate amount of folic acid (from 0.4 to 0.8 mg per day). Judging by epidemiological data, this substance helps to prevent defects in the neural tube, the rudiment of the brain and spinal cord in embryos. But it is not yet clear how folic acid affects this. Researchers have noted that it is involved in a complex network of metabolic reactions associated with neural tube growth.
And although folic acid is found in many foods, it is one of several nutrients that is better absorbed in synthetic form, in dietary supplements and food with an increase in its amount.
Several small studies have shown that calcium supplementation during pregnancy can reduce the risk of hypertension and preeclampsia. But to back up this information, larger studies need to be conducted.
There is still too little data on the benefits of taking omega-3 polyunsaturated fatty acids, vitamin D and multivitamins during pregnancy for the health of mother and child.
For healthy children and infants
Like healthy people, healthy children do not need multivitamins, and they need to avoid high doses of certain nutrients. Some studies suggest that omega-3 fatty acids may be beneficial in the treatment of hyperactivity disorder and autism, but there is not enough data for unambiguous conclusions.
The American Pediatric Academy and the Centers for Disease Prevention and Control recommend giving vitamin D supplements to infants during breastfeeding. The Academy also recommends iron supplements for them. Breast milk does not have enough of these nutrients. Children who eat special food usually get enough of these substances.
What not to take
The three categories of supplements that cause the greatest dissatisfaction on the part of experts and the FDA are supplements that help to lose weight, restore sexual function and increase results in sports and muscles. Among them, there are the most problems with dangerous, unmarked or simply illegal ingredients.
For example, in 2014, the FDA tested 21 "natural" dietary supplements, some of which claimed to help with weight loss, and found nine dietary supplements containing artificial compounds similar to amphetamines. Also last year, the FDA announced the recall of the dietary supplement, claimed as a means to improve muscle performance, after the discovery of anabolic steroids in their composition.
The FDA even has a general warning about the risks of bodybuilding products. "Many of these products are not dietary supplements at all; they are illegally marketed and unapproved medicines," said Kara Welch, chief advisor of the dietary supplements department at the FDA.
In a 2015 study, scientists from the Centers for Disease Control and Prevention (CDC) estimated that dietary supplements are the cause of 23,000 emergency department visits in the United States annually. Excluding cases of dietary supplements used by children without parental supervision, scientists concluded that the most dangerous additives were supplements for weight loss and tone enhancement.
But less suspicious supplements can also carry risks with them. Due to the lack of their approval by the FDA before entering the market and the content of plant components and imported ingredients in many additives, quality control can become a problem. In particular, dietary supplements had a problem with heavy metal contamination – for example, additives with a high lead content are constantly coming across.
The others
In between proven vitamins and muddy pills for weight loss, there are thousands of other formulations, tablets, extracts, elixirs and mixtures that supposedly benefit health. For most of them, there is very little data proving their safety or confirming their benefits. Many companies pass off inconclusive experiments on mice, rats, cell cultures, and experiments on a small number of people as evidence.
It may take decades for the data to confirm health-related claims. But what if these statements turn out to be true? Dietary supplements worth billions of dollars are sold by hope – and an unjustified attitude like "come on, it won't get any worse."
No, but really, what if the statements turn out to be true?
An excellent example is turmeric, and the ingredients of curry seasoning. For years, dietary supplement manufacturers and some researchers have claimed that turmeric helps with everything from inflammation and arthritis to cancer and Alzheimer's disease.
Its potential neurocognitive benefits have been the subject of several studies. Epidemiological data suggested that Indians who consume curry are less likely to have Alzheimer's disease, and the cognitive abilities of their elderly people are better on average. Recently, a small randomized study with a double-blind method and a control group found that the bioavailable form of one substance contained in turmeric, curcumin, can slightly improve verbal memory and attention in two out of seven tests. The trial was conducted for 18 months, and 40 elderly people who did not suffer from dementia participated in it. The results were published in The American Journal of Geriatric Psychiatry.
As Dr. Yuko Haara told us, this statistic is "minimally significant." Hara is the current director of the Aging and Alzheimer's Prevention team at the Alzheimer's Drug Discovery Foundation. The team aims to critically evaluate the latest data on Alzheimer's treatment in order to provide patients with the fastest and safest method of treatment.
In general, Hara said that this study found the same thing that other small studies have found – curcumin can slightly improve memory. But, as she notes, this is another small study, and "the statistics are not so reliable." It needs to be repeated with a large number of subjects to check whether the effect will persist. There was not enough data for the fund to raise the rating of curcumin among potentially useful substances.
Dr. John Ringman, a clinical neurologist at the University of Southern California, generally agrees with Hara. "The study is encouraging," he told us via email, but also noted the small size and small effects. "The real clinical impact of this improvement is unclear."
In 2012, Ringman was the lead author of a similar small study examining the cognitive effects of curcumin. Unlike the new study, they found no benefits. But, he says that "despite this, I take curcumin daily, because we found that depending on the dose size, we recorded a decrease in the number of complaints of joint pain. That's why I accept it."
Other preliminary data and small studies suggest that curcumin may help with knee pain that occurs with osteoarthritis. But the results are not final, and besides, there are certain doubts about its safety, Hara notes. Curcumin can affect the work of medications, such as aspirin, other painkillers, and diabetes medications.
How to choose?
Consult with your doctor about health and diet. If you decide to take dietary supplements supported by questionable or insufficient data, make sure that your doctor knows about it and will talk to you about safety. Many dietary supplements, like curcumin, can interfere with the work of other drugs and even affect the results of laboratory tests. For example, large doses of biotin (vitamin B7), which some take to improve the health of skin, hair and nails, can distort the results of tests related to heart attacks.
To make sure that the selected vitamins and dietary supplements are not contaminated with toxins and do not contain substances beyond those listed, choose a dietary supplement tested by independent companies (ConsumerLab.com , US Pharmacopeia, NSF International or UL). It's not a panacea, but experts say it's better than nothing. There are also companies, for example, LabDoor, checking dietary supplements for compliance with the label content.
For information on common dietary supplements, you can use a useful list from the Department of Dietary Supplements of the National Institute of Health.
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