What vitamin or mineral supplement do we need and which should be avoided?
Over half of the U.S. population take dietary supplements including vitamins, minerals, and herbs.
In 2021, Americans alone spent 50 billion dollars on dietary supplements.
For years many thought that supplements including vitamins and minerals were important for a healthy lifestyle, but what if this is not true and supplements can’t fill the nutritional gaps in our diet?
A review of 84 studies reveals that supplements are often a waste of money and some of them can be harmful to individuals.
The result is surprising as the case for supplements seems strong since foods such as nuts, fish, wholegrains, pulses, eggs, dairy, fruits, and vegetables are rich in nutrients with antioxidative and anti-inflammatory effects.
These nutritious foods have been shown to lower the risk of cardiovascular disease and cancer.
So, the idea that supplements can mimic the effect of vitamins and minerals in foods seems convincing.
However, micronutrients such as phytochemicals, vitamins, minerals, fibre in fruits and vegetables work together along with other nutrients to give the body what it needs.
Whereas these nutrients when extracted and used in isolation won’t have the same health effect as natural foods.
Dr Jeffrey Linder, the study’s senior author, said:
“Patients ask all the time, ‘What supplements should I be taking?’
They’re wasting money and focus thinking there has to be a magic set of pills that will keep them healthy when we should all be following the evidence-based practices of eating healthy and exercising.”
According to Northwestern Medicine scientists, there is not enough evidence for non-pregnant, otherwise healthy adults to take multivitamins or single or paired supplements.
In addition, the United States Preventive Services Task Force (USPSTF) guidelines recommend avoiding beta-carotene supplements as these may increase the odds of cancer.
They also advise against taking vitamin E as the supplement doesn’t reduce cardiovascular disease, cancer, or death from any cause.
Dr Linder said:
“The task force is not saying ‘don’t take multivitamins,’ but there’s this idea that if these were really good for you, we’d know by now.
The harm is that talking with patients about supplements during the very limited time we get to see them, we’re missing out on counseling about how to really reduce cardiovascular risks, like through exercise or smoking cessation.”
However, Dr Linder noted that dietary supplements such as vitamin D and calcium can help people with deficiency, for example, preventing bone loss in the elderly.
Or certain vitamins, such as folic acid (vitamin B₉) are vital during early pregnancy to prevent birth defects.
Dr Natalie Cameron, study co-author, said:
“Certain vitamins, such as folic acid, are essential for pregnant women to support healthy fetal development.
The most common way to meet these needs is to take a prenatal vitamin.
More data is needed to understand how specific vitamin supplementation may modify risk of adverse pregnancy outcomes and cardiovascular complications during pregnancy.”
The study was published in the JAMA (Jia et al., 2022).