5 Supplements That Could Be Harming Your Health

It might come as a surprise, but several widely used supplements could be silently doing damage to your health. In fact, five specific supplements have been shown in human research to provide little benefit and, in some cases, may increase risk of disease.

Let’s walk through the evidence, starting with one of the most common:

1. Calcium

Calcium is essential for muscle function, nerve signaling, and bone strength. But while it’s true that we need enough calcium—especially as we age—taking calcium in supplement form has been linked to some serious problems.

Several meta-analyses have shown that calcium supplements do not consistently reduce fracture risk, particularly in high-quality randomized trials. At the same time, calcium supplements have been linked to a significantly increased risk of heart attacks. One study even found a nearly 90% higher risk of heart attack among supplement users without adequate vitamin D. The reason may be that supplements can spike calcium levels in the blood, leading to buildup in artery walls. In contrast, calcium from food sources doesn’t seem to carry this risk and may even be protective.

Bottom line: Aim to get calcium from food (like dairy, leafy greens, and fortified plant milks) rather than supplements unless medically advised.

2. Iron

Iron is vital for transporting oxygen and maintaining energy. But supplementation can be risky if you don’t have a deficiency. Too much iron may interfere with zinc absorption, upset digestion, and even cause organ damage. Most healthy adults should get iron from their diet—meat, beans, leafy greens—rather than a pill.

Supplementation may be necessary in certain cases, like pregnancy, heavy periods, or diagnosed deficiency—but always under medical supervision.

3. Vitamin E

Often promoted for its antioxidant powers, vitamin E supplements have been heavily marketed as anti-aging and heart-healthy. However, the evidence doesn’t support these claims. In fact, large-scale studies suggest vitamin E supplements may increase the risk of death and possibly even prostate cancer.

A 300,000-person Cochrane review found no benefit—and a potential for harm. What’s more, vitamin E deficiency is incredibly rare, as the nutrient is abundant in nuts, seeds, oils, and green vegetables.

Takeaway: Skip the vitamin E supplements unless specifically prescribed.

4. Vitamin A

Another fat-soluble vitamin, vitamin A is important for vision and immunity. But too much from supplements has been associated with liver damage, bone weakness, and birth defects.

Just like vitamin E, vitamin A is plentiful in foods like carrots, sweet potatoes, and leafy greens. Most people get enough from their diet, and deficiency is rare.

5. Resveratrol

Resveratrol—a compound found in red wine and grapes—was once hailed as a miracle anti-aging molecule. Early lab studies sparked excitement, but later research has failed to support those claims. Resveratrol doesn’t appear to activate the key longevity genes scientists hoped it would.

Worse, some studies show that resveratrol may blunt the benefits of exercise and lower testosterone levels. The idea that this supplement boosts lifespan or metabolic health just doesn’t hold up.

The Safer Approach

Health is complex, and more is not always better—especially when it comes to supplementation. While specific individuals may benefit from certain supplements, the general public is often better off getting nutrients from food, not pills.

If you’re concerned about your nutrient intake or bone health, consider getting tested and working with a healthcare provider to determine your actual needs.

And if you’re curious about the best science-backed strategies for long-term health, sleep, energy, and weight management, stay tuned. New research emerges every week—and we’re here to help you make sense of it.

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