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- Ketogenic diet, by replacing glucose with ketones as an energy source, lessens alcohol cravings among people with alcohol use disorders.
- Omega-3 fatty acids reduce the risk of cardiovascular disease-related death by up to 23 percent, especially in people with high triglyceride levels.
- Women see a 24 percent drop in premature death risk with just 140 minutes of weekly activity – half the time men need for similar benefits.
- Aging undermines the brain's capacity for maintaining working memory, with subtle declines in neuron activity and connectivity in the prefrontal cortex.
Vitamin D, a fat-soluble nutrient, is sequestered in adipose tissue, limiting its circulation—an effect amplified in obesity. Obese adults, for example, exhibit a 57 % smaller rise in circulating vitamin D₃ after whole-body ultraviolet exposure and are more than half as likely to reach sufficient vitamin D levels than normal-weight adults. Against this backdrop, the VitaDEx randomized trial showed that ten weeks of indoor exercise during winter sharply attenuated seasonal vitamin D loss and fully preserved its active hormone, 1,25(OH)₂D₃—without weight loss or supplementation.
- Active hormone maintained: Exercise fully prevented the winter decline in 1,25(OH)₂D₃, while controls experienced a 15 % drop. (The precursor 25-hydroxy-vitamin D fell only 15 % in exercisers versus 25 % in sedentary controls.)
- Adipose sequestration puzzle: Contrary to expectations, adipose vitamin D concentrations remained largely unchanged. “Exercise did not drive a greater decrease in adipose tissue concentrations of vitamin D…there was no correlation between the change in serum 25(OH)D and changes in adipose vitamin D₃ concentrations.”
- Mechanistic pivot: Researchers suggested possible transient vitamin D mobilization, depot-specific effects, or direct metabolic adaptations improving vitamin D efficiency. They speculated that regular physical activity might enable “more ‘efficient’ vitamin D metabolism, making better use of the available substrate to generate the active metabolite without tipping the balance into a negative feedback loop.”
Taken together, the findings indicate exercise is not merely releasing vitamin D from fat stores; it is altering the flux and enzymatic handling of the hormone, offering a route to restore endocrine availability where supplementation often fails in obesity.
Press Release: Regular Exercise Helps Maintain Vitamin D Levels During Winter
Study: Exercise without Weight Loss Prevents Seasonal Decline in Vitamin D Metabolites: The VitaDEx Randomized Controlled Trial
High sodium intake raises blood pressure, while high potassium intake tends to lower it. However, these effects vary between men and women in ways that scientists do not yet fully understand. A recent study found that biological sex differences may influence how sodium and potassium affect blood pressure regulation, with the kidneys playing a crucial role in mediating these responses.
Researchers developed sex-specific computer models that simulate how the body regulates sodium, potassium, fluids, and blood pressure. These models incorporated key systems involved in this process, such as the kidneys, blood vessels, digestive system, and hormones that help manage blood pressure. The simulations accounted for known differences between men and women in kidney function, hormone responses, and nerve activity.
The models revealed that women’s blood pressure rises less than men’s in response to a high-sodium diet. This muted response appears to be due to differences in kidney transporter proteins, which control how the kidneys reabsorb sodium and potassium. However, when potassium intake increased, the models predicted a robust response wherein more potassium and sodium are excreted in urine, resulting in a substantial drop in blood pressure, even when sodium intake remains high.
These findings suggest that women possess a built-in advantage in managing high-sodium intake, likely due to differences at the kidney level. They also support increasing dietary potassium as an effective strategy for lowering blood pressure. Learn more about sodium needs in Aliquot #124: How much sodium do you actually need?
Plastic contamination has become pervasive, with microplastics—microscopic plastic particles—now detected in most human tissues. A recent study found microplastics in the follicular fluid of women undergoing fertility treatment, raising new concerns about how these contaminants might affect human reproduction.
Researchers collected follicular fluid samples from 18 women receiving assisted reproductive treatment. To detect and characterize plastic particles smaller than 10 micrometers, they used scanning electron microscopy paired with energy-dispersive X-ray spectroscopy—an advanced technique that identifies materials based on their composition.
They found microplastics in nearly 80% of the samples (14 out of 18), with an average concentration of more than 2,000 particles per milliliter. On average, particles measured about 4.5 micrometers in diameter. They did not identify an association between microplastic concentration, fertilization, miscarriages, and live birth. However, higher microplastic concentrations were associated with higher levels of follicle-stimulating hormone, a key marker of ovarian function.
These findings indicate that microplastics accumulate in human ovarian follicles. The investigators proposed that the lack of association between microplastics and aspects of reproductive health may have been due to the small study size (only 18 women), especially in light of animal evidence indicating that microplastics disrupt hormone regulation, impair egg maturation, and alter embryo development. Learn more about the effects of microplastics on the reproductive system in this episode featuring Dr. Rhonda Patrick.
