Fermented foods such as yogurt, kefir, kimchi, sauerkraut, miso, tempeh, and natto can be a valuable part of a longevity-focused diet. While they have not been proven to directly extend lifespan, they may support gut microbiome diversity, cardiometabolic health, glucose regulation, blood pressure, lipids, and inflammation in some people. The strongest evidence suggests fermented foods are best viewed as a supportive dietary habit rather than a stand-alone longevity treatment. I recommend including them regularly if they are well tolerated, while paying attention to added sugar, sodium content, histamine sensitivity, and overall diet quality.

Urolithin A is a gut microbiome-derived compound produced from polyphenols found in foods such as pomegranate, berries, and nuts. Its longevity interest comes from its potential ability to stimulate mitophagy, the process of clearing damaged mitochondria. Early research suggests urolithin A may support mitochondrial health, muscle endurance, and certain inflammatory markers, but human studies remain short and limited. There is currently no evidence that urolithin A extends lifespan or prevents major age-related diseases in humans. For now, I view it as a promising mitochondrial-health supplement that may have a role in selected patients as part of a broader lifestyle and longevity protocol — not as a proven anti-aging therapy.

The Galleri test is a blood-based multi-cancer early detection test that analyzes cell-free DNA methylation patterns to look for a cancer signal across more than 50 cancer types. It is one of the more promising developments in cancer screening, especially for cancers that do not currently have standard screening tests. However, Galleri is not FDA-approved, has limited sensitivity for early-stage disease, can miss cancer, can lead to false positives and additional workups, and has not yet been proven to reduce cancer mortality in the general population. For now, I view it as an optional tool for selected patients in highly personalized preventive care — not a routine screening test for everyone — and it should complement, not replace, proven cancer screening.

Caffeine and coffee can have different effects on glucose metabolism. Caffeine by itself may acutely reduce insulin sensitivity and temporarily raise glucose in some people, especially around meals, stress, poor sleep, or morning cortisol. However, habitual unsweetened coffee consumption is consistently associated with lower risk of impaired glucose tolerance and type 2 diabetes, including in studies of both caffeinated and decaffeinated coffee. For most people with prediabetes, moderate coffee can fit into a healthy lifestyle, but it should not worsen sleep, anxiety, reflux, blood pressure, or glucose control — and it should not be turned into a sugary drink.

PDE5 inhibitors such as sildenafil, tadalafil, and vardenafil are established medications used for erectile dysfunction and certain vascular conditions. Emerging observational and preclinical research suggests they may be associated with lower colorectal cancer risk and possibly improved colorectal cancer outcomes, but this evidence remains hypothesis-generating rather than practice-changing. No randomized trial has proven that these medications prevent or treat cancer, and concerns such as confounding, healthy-user bias, and a possible melanoma signal mean they should not be used for cancer prevention outside of appropriate medical indications or clinical trials.

Vitamin C is essential for collagen production, immune function, antioxidant defense, wound healing, and blood vessel health. While supplementation may modestly shorten common cold duration and slightly lower blood pressure, it is not proven to extend lifespan or replace the benefits of a plant-rich diet. For most healthy adults, vitamin C is best obtained from whole foods like citrus, berries, kiwi, bell peppers, broccoli, and leafy greens, which provide fiber, polyphenols, potassium, and other protective compounds beyond vitamin C alone.

Coffee is consistently associated with longevity benefits in observational studies, with moderate intake around 3 cups per day appearing reasonable for many adults. It may support cardiovascular, metabolic, liver, and brain health, but caffeine sensitivity, sleep disruption, anxiety, reflux, and cholesterol effects from large amounts of unfiltered coffee are important limitations. The healthiest approach is to drink coffee mostly black, avoid sugary additions, choose filtered coffee when cholesterol is a concern, and use it to support—not replace—a healthy lifestyle.

Quercetin is a flavonoid found in plant foods such as onions, apples, berries, tea, herbs, and leafy greens. Supplement studies suggest modest benefits for blood pressure, inflammation, and some lipid markers, but the evidence remains limited by small trials, short duration, poor bioavailability, and inconsistent results. For most people, the better strategy is not isolated quercetin supplementation, but eating more whole plant foods that naturally contain quercetin along with fiber and many other protective compounds.

Spermidine is a naturally occurring compound found in foods such as wheat germ, soybeans, mushrooms, legumes, aged cheese, and fermented foods. It has gained attention for its role in autophagy, mitochondrial health, immune function, and cellular repair. While animal studies and observational human data are promising, spermidine supplementation has not yet been proven to extend lifespan in humans, and larger long-term trials are still needed.

Activated charcoal has an evidence-based role in emergency medicine for certain acute poisonings, but that does not make it a proven daily detox supplement. Wellness claims around mold detox, heavy metals, bloating, hangovers, and longevity are not supported by strong clinical evidence. Regular use may also interfere with medication and nutrient absorption, making it a supplement to approach with caution.

GlyNAC, a combination of glycine and N-acetylcysteine, is an emerging longevity supplement designed to support glutathione production, mitochondrial function, and cellular stress resilience. Early animal and human studies suggest potential benefits for oxidative stress, inflammation, insulin resistance, cognition, and physical function in older adults. However, GlyNAC has not been proven to extend lifespan in humans, and larger long-term studies are still needed.

Juicing can be a convenient way to increase vitamins, minerals, polyphenols, and other plant compounds, especially for people who struggle to eat enough vegetables. However, juicing removes much of the fiber, can concentrate sugar and calories, and should not be used as a cleanse or detox. Whole fruits and vegetables should remain the foundation.

Potassium bromate is a controversial flour additive used to strengthen dough and improve bread texture. Although it remains permitted in some U.S. foods, it has been linked to cancer, kidney toxicity, oxidative stress, and DNA damage in experimental studies. Learn where it may be found and how to avoid it by choosing unbromated flour and less processed baked goods.

Phthalates are common chemicals found in plastics, fragrances, personal care products, food packaging, household dust, and some medications. They have no known health benefit and may affect hormones, fertility, pregnancy, child development, metabolism, and thyroid function. Learn practical ways to reduce exposure without living in fear.

Nitric oxide plays an important role in blood vessel health, circulation, blood pressure, and exercise performance. Beetroot and nitrate-rich vegetables may help support nitric oxide production, but the strongest approach is still food-first: leafy greens, beets, exercise, and overall cardiovascular prevention before relying on supplements.

Fluoride can help prevent cavities, but total exposure matters — especially for young children. This article reviews the benefits of community water fluoridation, fluoride toothpaste, and dental treatments, while also discussing concerns about excessive exposure, dental fluorosis, thyroid and bone effects, and ongoing research on neurodevelopment.

Gardening is more than a hobby — it is a lifestyle habit that supports movement, nutrition, stress reduction, sunlight exposure, mental health, and connection to nature. Research suggests gardening is associated with lower mortality and better cardiovascular, metabolic, and emotional well-being, making it a powerful example of lifestyle medicine in action.

Sea moss has become a popular wellness supplement for gut health, thyroid support, immunity, and longevity. While it contains minerals, iodine, and promising bioactive compounds, strong human evidence is limited — and excessive iodine intake, thyroid effects, heavy metals, and product quality are important concerns.

Glutathione is one of the body’s most important antioxidant and detoxification molecules, supporting cellular repair, immune function, and mitochondrial health. While glutathione levels decline with age, current evidence does not show that supplementation extends lifespan — making diet, exercise, sleep, and metabolic health the foundation.

Soy is often criticized for its potential effects on hormones, but the evidence is far more reassuring than the hype suggests. Whole soy foods like tofu, tempeh, edamame, and unsweetened soy milk can be part of a healthy, longevity-focused diet, while high-dose soy supplements and ultra-processed soy products deserve more caution.