Centenarians Show a Distinct Metabolic Profile Tied to Bile Acids and NAD+
People who live past 100 have a unique metabolic fingerprint. In a study of 213 participants from the New England Centenarian Study, extremely long-lived individuals had higher levels of certain bile acids and lower levels of bilirubin compared to younger controls. Higher bile acid and steroid levels were linked to lower mortality risk. The researchers also built a "metabolomic clock" that estimates biological age, and deviations from it predicted death risk.
Key Insight
This study suggests bile acid metabolism and NAD+ pathways may be key targets in longevity research.
Related Studies
We May Not Be Aging Slower. We're Just Starting Later.
A big question in longevity research is whether rising life expectancy means we're actually aging more slowly. This analysis of mortality data from 12 countries suggests the answer is no. After accounting for historical shocks like wars and pandemics, the rate at which aging accelerates after 80 hasn't changed. The gains in lifespan appear to come from pushing back when serious aging begins, not from slowing the process itself.
Metformin's Anti-Aging Case: Strong Clues but Still No Proof
This review pulls together lab, population, and clinical trial evidence on metformin as a potential aging-slowing drug. At normal doses, metformin seems to flip several key aging switches: boosting cellular cleanup, calming inflammation, and improving energy production. Large population studies link metformin use to lower rates of age-related diseases, even in people without diabetes. However, the review honestly notes that metformin may actually worsen aging in older animals, so the picture is still mixed.
Fat Tissue Controls Lifespan Through Insulin Signaling in Fruit Flies
In fruit flies, dialing down a gene called Dicer-1 in fat tissue extended lifespan. It worked even when flies were already on calorie restriction. The mechanism involves a chain reaction: lower Dicer-1 reduces a small RNA molecule in fat, which boosts a hormone that then tells the brain to release less insulin. Less insulin signaling is a well-known longevity pathway across species.
Disclaimer: Research summaries are provided for informational purposes only and do not constitute medical advice. Always consult a qualified healthcare professional before making changes to your health routine.