In 1954, biochemist Dr. Denham Harman proposed the “Free Radical Theory of Aging,” hypothesizing that people age because our metabolic processes produce free radicals—unstable molecular compounds.

But later, in 2018, physiologist Dr. José Viña and his colleagues unveiled “A Free Radical Theory of Frailty,” arguing that free radicals do not necessarily dictate how long you’ll live but instead causes frailty in older people—a decline in wellbeing, unintentional weight loss, reduced grip strength, lowered walking speed, and difficulties standing.

No matter which theory correctly explains why your body ages and deteriorates, many scientists agree that an increase in free radicals and a decline in the body’s ability to combat them causes a significant decline in your cellular health.

Free radicals and oxidative stress.

Free radicals are essentially unstable atoms that can damage cells, cause illness, and contribute to expedited aging. They can wreak havoc on DNA, cellular proteins, and cell membranes by stealing their electrons via a process known as oxidation.

Oxidation is a normal, necessary process in the body. But when overexposure to free radicals complicates the usual oxidation process and produces oxidative stress, that’s when you’re in trouble.

Oxidative stress occurs when an activity imbalance develops between the free radicals and antioxidants in your system.

How do we get stressed on a cellular level?

Inside every living cell in your body, small organelles called mitochondria constantly generate the energy your cells need to function. Designated “the powerhouses of the cell,” mitochondria convert food into cellular energy. But during this metabolic process, mitochondria also produce a byproduct—free radicals.

When your body needs a lot of energy, your mitochondria kick into overdrive, generating more free radicals.

Factors like lack of sleep, lack of exercise, poor diet, drinking, smoking, and sun exposure can all lead to oxidative stress due to your mitochondria producing excess energy to counter these events.

How to fight cellular stress.

An effective way to reduce the effects of oxidative stress is to supplement your mitochondria with key micronutrients to help keep them in shape.

Foods that are rich in antioxidants, such as alpha-lipoic acid and coenzyme Q10, can help offset the antioxidant imbalance and keep your free radicals at a safe level. These can be found in fruits, vegetables, and other foods containing high levels of vitamins C and E.

Other micronutrients are harder to supplement with regular foods. Nicotinamide riboside is a particularly helpful micronutrient that is only found in trace amounts in milk and yeast. It elevates our NAD+, a vital coenzyme needed for healthy cell function.

A study in the scientific journal, Redox Biology, demonstrates that keeping NAD+ levels balanced helps counteract oxidative stress, by bolstering the body’s restorative cellular processes.

Complimenting healthy foods with an NAD+ boosting supplement, like nicotinamide riboside, can help provide additional support for your cells from events that cause oxidative stress.

It’s important to keep consistent with your intake. Preventive cellular care requires you to be proactive about your daily cellular nutrition.