These four popular longevity supplements may be doing more harm than good — here’s what dietitians want you to know before your next trip to the vitamin aisle.

The supplement aisle has a way of making everyone feel like they’re one capsule away from eternal youth. Promises of boundless energy, glowing skin, sharper memory and stronger bones line every shelf — and it’s hard not to reach for something, anything, that feels like an investment in your future self. But what if some of those bottles were quietly working against you?

The truth is, not all supplements earn their place in a wellness routine. While certain nutrients are worth supplementing under the right circumstances, taking the wrong ones — especially without medical guidance — can interfere with your body’s natural processes, interact with medications or create health risks you never saw coming. Dietitians are sounding the alarm on four supplements in particular that people commonly reach for in the name of healthy aging.

1. Iron

Iron is a critical mineral — it keeps red blood cells healthy and ensures oxygen moves efficiently through the body. But reaching for an iron supplement without a doctor’s recommendation is a risk not worth taking.

Unless there’s a confirmed deficiency or a specific medical condition, unnecessary iron supplementation can be dangerous. Excess iron has the potential to accumulate in vital organs, including the liver, heart and pancreas — a concern that’s especially serious for people with hemochromatosis, an inherited condition that causes the body to absorb iron in excess. This condition affects approximately one in 200 to 400 people and often goes undetected. Beyond organ damage, excess iron can also reduce the effectiveness of certain medications.

There are cases where older adults — particularly those managing iron-deficiency anemia from chemotherapy or gastrointestinal conditions like celiac disease — do require iron supplementation. But for generally healthy individuals, it’s not a longevity strategy. It’s an unnecessary gamble.

2. Supplements Containing Resveratrol

Resveratrol, the antioxidant compound naturally found in grapes, red wine and some berries, has been heavily marketed as a longevity powerhouse. The reality is far less glamorous.

While animal studies have produced some intriguing findings, the doses required to replicate those effects are dramatically higher than what’s found in any commercially available supplement. Current research has not produced conclusive clinical evidence to support resveratrol as a legitimate recommendation in any health care setting. High-dose resveratrol supplements may also interact with blood thinners and trigger gastrointestinal side effects. For now, the science doesn’t justify the hype — and the potential risks make it a supplement best left on the shelf.

3. High-Dose Vitamin C

Vitamin C is genuinely essential. It supports immune health, skin integrity and the absorption of plant-based iron — and as a powerful antioxidant, it helps defend cells against free radical damage. But there’s a meaningful difference between getting vitamin C through food and flooding the body with megadose supplements.

Research suggests that excessively high levels of externally introduced antioxidants — vitamin C included — may actually suppress the body’s own internal antioxidant system, which is naturally far more effective at combating oxidative stress. The body also tightly regulates how much vitamin C it absorbs, and any surplus is typically excreted rather than used, offering no real benefit. What it can cause, however, is gastrointestinal discomfort. More vitamin C does not mean better protection.

4. Vitamin E

Vitamin E is a fat-soluble antioxidant that protects cells from oxidative damage — and it’s a nutrient the body genuinely needs. The problem is with supplementing it in isolation at high doses.

Studies exploring whether vitamin E supplements can extend life span have returned mixed results at best. More concerning, research has suggested that high supplemental doses could disrupt the body’s natural oxidative balance and potentially raise the risk of cardiovascular issues or certain cancers. When antioxidants are consumed in concentrated, isolated amounts rather than as part of a whole-food diet, they can interfere with normal cellular processes — producing the opposite of the intended effect.

Building a Longevity Lifestyle

Real, lasting wellness doesn’t come in capsule form. Dietitians consistently point to the same foundational habits as the true drivers of healthy aging:

• Eat a colorful, whole-food diet rich in fruits, vegetables, whole grains, lean proteins and healthy fats
• Move your body regularly — walking, dancing, swimming or yoga all count; the goal is consistency
• Prioritize quality sleep — seven to nine hours per night supports the body’s repair processes
• Stay mentally engaged through reading, puzzles or learning new skills to support cognitive health
• Drink enough water throughout the day for digestion, skin health and overall energy
• Maintain meaningful social connections — emotional well-being is a cornerstone of longevity

Before adding any supplement to your routine, have a conversation with a health care professional. The supplement industry is not required to prove its products work before selling them to you — that burden falls on consumers to investigate. By prioritizing whole foods, proven lifestyle habits and evidence-based guidance over marketing claims, aging well becomes far less complicated than the vitamin aisle would have you believe.

Source: EatingWell