Both the American Cancer Society and the American Heart Association have confirmed that taking vitamins in large quantities offers no more benefit to the body than a healthy diet.
The British newspaper, The Mirror, quoted the two associations as saying that our bodies do not adequately absorb vitamins and minerals from pills and capsules.
They explained that our bodies are designed to first recognize nutrients from food, and therefore there is no need to spend a lot of money on something that will not be effective and has no therapeutic effect. The associations warned against the growing dietary supplement industry and our susceptibility to promotional advertising, noting that, with the exception for pregnant women, some elderly individuals, and those following a doctor's orders, no one should take these substances.
They added that everything we need in supplements is already present in our food, and emphasized that once-a-day vitamin supplements have no role in preventing cancer or heart disease.
Instead, doctors from both associations recommended following a balanced diet with a variety of foods, which is more effective than any capsule.
For example, for vitamin D, especially in older adults, the recommended daily intake is 1,000 IU to ensure adequate absorption of calcium and phosphorus from the diet, which is essential for maintaining strong bones. However, there is no evidence that vitamin D supplements prevent fractures.
Doctors have also cautioned against calcium supplements, as they increase the risk of heart attack by 30%. These supplements can also lead to kidney stones and digestive problems.
Doctors pointed to a 2023 study of over 12,000 patients at risk of heart attack who did not receive adequate protection despite taking fish oil supplements. Another major study that same year linked fish oil supplements to an increased risk of prostate cancer.