With the return of the cold, some people already anticipate the arrival of winter illnesses. And equip yourself with a supposed preventive pharmacopoeia: food supplements, vitamins, propolis cure or essential oils in the hope of escaping nasopharyngitis, bronchitis, sinusitis and seasonal angina… But is it really effective? We put the question to two doctors.
• Food supplements, a “placebo effect”?
“Reinforced immunity”, “physical reinforcement”, “immune defenses”… Food supplements that offer to “reinforce” or “stimulate” the immune defenses are legion, in the form of tablets, gummies or drops: more than half of the The French population has already taken it, according to an Opinionway poll. And the market is growing: +6% in 2021, indicates the National Union of Food Supplements.
Its components are multiple: based on melatonin, pale pink powder, California poppy and lemon balm extract, for example, for those that promise to improve sleep; vitamin B6, B8, zinc and hyaluronic acid for those who claim to strengthen hair; or carob, cherry stems, chromium and ascophyllum for which they are supposed to reduce fat absorption.
These supplements are defined by the Ministry of Health as “food products that are intended to supplement a normal diet and that constitute a concentrated source of nutrients or other substances with nutritional or physiological effect.”
But “none have shown efficacy beyond the placebo effect,” warns general practitioner Corentin Lacroix. Otherwise, “we would prescribe a shovel”, says the author of the YouTube channel WhyDoc, distinguished by the Academy of Medicine for the pedagogy of its content.
The Ministry of Health also recalls that “the substances that make up food supplements do not have a therapeutic action and are not intended to prevent or cure a disease.”
Corentin Lacroix is also concerned about possible “cocktails” of food supplements ingested simultaneously: a first for immune defenses, a second for hair growth or skin quality, and a last supposedly to promote sleep. “From a marketing standpoint, it’s very well done,” he tells BFMTV.com. “But there is a real risk in taking too much and telling yourself it will be good for you. However, this is not necessarily the case.”
• Vitamins, “useless”?
A vitamin A, C or E cure to face the winter? A multivitamin and mineral complex to sneak between the cracks of viruses? It’s “useless,” says Boris Hansel, an endocrinologist and nutritionist at Bichat Hospital, taking a cue from vitamin C. “Vitamin C deficiency is completely prevented by diet if we follow the recommendations,” he told BFMTV.com. “Especially since we don’t store it. Overloading it won’t have any effect.”
The consumption of vitamin C is essential: it is involved in nerve transmission, has a protective role in tissues and facilitates the absorption of non-heme iron, explains ANSES. But the professor of medicine recommends one or two kiwis added to a citrus fruit to cover daily vitamin C needs, that is, 110 mg per day, rather than a 1000 mg tablet, as some products propose.
“A food supplement that is absorbed suddenly does not have the same effects as a food, which is a combination of micronutrients,” he explains, warning of overdoses, especially in the case of vitamin E -with antioxidant properties- or supplements of calcium or iron that are not negligible if not necessary.
“Telling yourself that you are going to take vitamins to have a better winter is a figment of the imagination. If it takes more than a month there is no danger, nor is there any gain”.
With the exception of vitamin D, points out Boris Hansel, who dedicated a video to it: the majority of the French do not consume enough of it, according to ANSES. However, it is particularly important, since it allows in particular to fix calcium and phosphorus in the body, also reminds the Agency.
• Royal jelly, propolis, pollen… “Marketing”?
Royal jelly, propolis or pollen cures to expel microbes and strengthen white blood cells? In a blister, pure or in chewing gum?
“Marketing”, says Dr. Corentin Lacroix again. “Only honey potentially has a small effect in persistent dry cough,” he believes, although it should be avoided in children under 1 year of age due to the risk of botulism. “And be careful with pollen, which can be allergenic,” he adds.
For the endocrinologist and nutritionist Boris Hansel, the only advantage of these cures is that patients take care of themselves. “And when they take care of themselves, they pay more attention to what makes them feel good,” he says. “So if someone feels they get less sick from having a spoonful of honey or royal jelly every morning, so much the better.”
• Essential oils, ineffective in seasonal diseases?
Ravintsara, eucalyptus, tea tree, niaouli or cinnamosma… There are those who bet on essential oils to which they attribute antiviral, immunostimulant or even antibacterial properties. Dr. Boris Hansel calls for caution: “There is no scientific evidence of the effectiveness of essential oils in seasonal diseases.”
Especially since they can be potentially toxic. Check Prescribe alerted on the subject, pointing out the risks of acute poisoning, particularly by ingestion, ranging from digestive and neuropsychic disorders to kidney failure and liver damage.
Boris Hansel also encourages vigilance about the content of these essential oils, especially for pregnant women or children. “You shouldn’t take just anything,” he insists.
ANSES has also warned about essential oil aerosols and diffusers, denouncing cases of irritation and considering that these products could emit volatile organic compounds that could “constitute a source of indoor air pollution.” The Agency also warned against food supplements containing tea tree, niaouli and cajeput essential oils, which pose neurological, carcinogenic, genotoxic and potentially reprotoxic risks.
• Barrier gestures, the best prevention
For Corentin Lacroix and Boris Hansel, certain gestures are really effective in not getting sick: “These are simply barrier gestures,” recalls the former. “Ventilation, hand washing, coughing into your elbow and wearing a mask are our best allies,” he insists. Boris Hansel also adds sleep and physical activity to the list.
“It is scientifically proven: sleeping poorly lowers the immune system. And we know that physical activity prevents many pathologies. That is really effective for not getting sick.”
As for food, if Corentin Lacroix recommends the Mediterranean diet to stay healthy, especially from the point of view of cardiovascular diseases, no daily intake of fruits or vegetables will prevent catching a cold.
At this point, this youtuber doctor is also concerned about a certain rigorous vision of food. “Some patients impose so many dietary restrictions to stay healthy that they fall into what is called orthorexia.” An eating disorder related to the quality of food, or when eating healthy becomes an obsession.
Source: BFM TV
