Dr. Susan Carter, MD: Endocrinologist & Longevity Expert

Can low testosterone cause joint pain?

Dec 06, 2025 · 15 min read

Low testosterone can contribute to joint pain by increasing chronic inflammation and weakening the muscle, bone, and cartilage support that stabilizes joints. A 2025 longitudinal cohort study in BMC Musculoskeletal Disorders reported that men with low testosterone had about double the risk of developing osteoarthritis. [4] If aching knees or stiff shoulders come with fatigue, ...

Which essential biomarkers runners should track? The lab numbers that predict fatigue and low testosterone

Dr. Susan Carter, MD: Endocrinologist & Longevity Expert

Dec 04, 2025 · 15 min read

The essential biomarkers runners should track include vitamin D, iron and ferritin, magnesium and potassium, C reactive protein, testosterone, cortisol, blood glucose, and performance markers like VO2 max, lactate threshold, and resting heart rate. When those numbers drift, your training can feel harder, recovery slows, and injury risk rises even if your mileage looks “perfect.” ...

BPC-157 FDA status in 2026: Compounding and legality

Dr. Susan Carter, MD: Endocrinologist & Longevity Expert

Dec 03, 2025 · 13 min read

As of 2026, BPC-157, CJC-1295, and ipamorelin are not FDA-approved drugs, and all appear on the FDA’s Section 503A “Category 2” list (FDA Category 2 list, accessed February 15, 2026). Thymosin beta-4, which is often marketed online under the nickname “TB-500,” also appears on the FDA’s Section 503A “Category 2” list (FDA Category 2 list, ...

Do runners live longer? The science behind mileage and mortality

Dr. Susan Carter, MD: Endocrinologist & Longevity Expert

Dec 03, 2025 · 16 min read

In long-term studies, running as little as 5 to 10 minutes a day at an easy pace is linked to roughly a three-year longer lifespan and about a 27% lower risk of all-cause mortality versus not running. The sweet spot for longevity appears to be moderate weekly volume (around 2 to 3 hours), not marathon-level ...

Testosterone killing foods: What actually lowers T in men and what to eat instead

Dr. Susan Carter, MD: Endocrinologist & Longevity Expert

Dec 03, 2025 · 17 min read

“Testosterone killing foods” are foods that, when eaten often as part of an ultra processed Western style diet, are linked to lower testosterone in men through inflammation, insulin disruption, and weight gain. The good news is that you do not need a perfect diet. You need a few high impact swaps and the right lab ...