A new U.S. Army study shows that waist circumference and belly fat are far stronger determinants of circulating testosterone levels than aging.


An image from a previous publication authored by Dr. Karl E. Friedl, one of the U.S. Army scientists on the current study. 

Aging &amp; Longevity

Protein Restriction and Longevity: Can Limiting Protein Intake Support Healthy Aging?

University of Wisconsin researchers examine how reducing dietary protein intake may reshape nutrient sensing, metabolism, mitochondrial function, and other pathways linked to healthier aging.

(One of the leading authors on the Cell Press Blue article, Dr. Dudley Lamming | University of Wisconsin)

Researchers examine how restricting protein intake can improve metabolic health and influence aging-related pathways to extend healthspan and lifespan.

The Overlooked Organ That Could Hold the Key to Fighting Aging

Scientists are researching ways to regrow the thymus, an immune organ that vanishes with age, to suppress the tolls of aging.

(The thymus [colored orange] is located in the upper chest | NAD.com)

An organ involved in immunity, the thymus, vanishes as people get older, and scientists are researching ways to regrow it to fight aging.

Immunity

<p><span style="font-weight: 400;">Model: C57BL/6J mice </span></p>
<p><span style="font-weight: 400;">Dosage: Eating only within an 8-hour window and fasting for 16 hours (~20% caloric deficit may be required) </span></p>


Restricting food intake for 16 hours a day improves the health of female mice and moderately prolongs the life of male mice. 

The principal investigators of the study (from left to right): Dr. Carla Green, Dr. Victoria Acosta-Rodriguez, and Dr. Joseph Takahashi (image: dallasnews.com). 

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<p class="PDq2pG_selectionAnchorContainer" data-start="0" data-end="125">Model: 4-week-old <span class="hover:entity-accent entity-underline inline cursor-pointer align-baseline"><span class="whitespace-normal">SM/J</span></span> mice (with <span class="hover:entity-accent entity-underline inline cursor-pointer align-baseline"><span class="whitespace-normal">C57BL/6J</span></span> comparison mice)</p>
<p data-start="127" data-end="279" data-is-last-node="" data-is-only-node="">Dosage: Weekly intraperitoneal injections of 40 mg/kg Navitoclax or 5 mg/kg Dasatinib + 50 mg/kg Quercetin from 4 to 6–8 or 17 weeks of age.</p>
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Dasatinib and Quercetin Delay Early-Onset Disc Degeneration in Mice

Researchers find that clearing senescent cells preserves disc structure and slows early-onset disc degeneration in mice.


Search Result: Body composition

Why Low Testosterone Isn’t Just About Getting Older: New U.S. Army Findings Point to Belly Fat

Protein Restriction and Longevity: Can Limiting Protein Intake Support Healthy Aging?

The Overlooked Organ That Could Hold the Key to Fighting Aging

16-Hour Intermittent Fasting Improves Health and Longevity, New Study Confirms

Dasatinib and Quercetin Delay Early-Onset Disc Degeneration in Mice