Dr. Susan Carter, MD: Endocrinologist & Longevity Expert

Healthy carbonated drinks: The science behind the switch for men

Jan 13, 2026 · 9 min read

Switching from sugar-sweetened soda to low- or no-sugar functional carbonated drinks removes the liquid fructose hit that drives insulin resistance and visceral belly fat (which can suppress testosterone) and can add prebiotic fibers like inulin that feed beneficial gut bacteria such as Bifidobacteria. “Healthy” on the can isn’t a guarantee—here’s how the key ingredients actually ...

The mitochondrial theory of aging: Why your cells lose power and how to fix it

Dr. Susan Carter, MD: Endocrinologist & Longevity Expert

Jan 13, 2026 · 12 min read

Between ages 30 and 70, mitochondrial function in skeletal muscle can drop by 25–30%, lowering ATP production and slowing repair, fat metabolism, and hormone output—changes many researchers consider a core driver of aging. The good news is that mitochondria can respond to the right signals, and this guide shows how to recognize dysfunction and rebuild ...

Should I lose weight before building muscle? A men’s guide to getting leaner without losing strength

Dr. Susan Carter, MD: Endocrinologist & Longevity Expert

Jan 11, 2026 · 12 min read

Most men don’t need to “lose weight first” — a moderate calorie deficit paired with progressive resistance training and high protein can reduce body fat while preserving, and sometimes adding, lean mass by maintaining muscle protein synthesis. The key is getting leaner without the metabolic slowdown and strength loss that often come with aggressive cutting, ...

Gut health and weight loss: The science behind why some men struggle to lean out

Dr. Susan Carter, MD: Endocrinologist & Longevity Expert

Jan 09, 2026 · 10 min read

Lower gut microbiome diversity and certain microbiota patterns (including a higher Firmicutes-to-Bacteroidetes ratio in some studies) are associated with increased “energy harvest” from food and altered metabolite-driven appetite and metabolic signaling, which can make fat loss harder even when calories are similar. Here’s how the gut–metabolism connection shows up in real life and what to ...

Can you chew gum while fasting? What it means for ketosis and autophagy

Dr. Susan Carter, MD: Endocrinologist & Longevity Expert

Jan 08, 2026 · 9 min read

Sugar-free gum is usually compatible with a ketosis-focused fast because one piece is typically a negligible caloric input (often kept under ~30 calories total during the fasting window), but any calorie- or sugar-containing gum can blunt a stricter fast aimed at autophagy, where the safest approach is staying truly calorie-free. The key is how many ...