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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.
A consistent daily schedule may do more than support sleep—it could also help maintain physical fitness as we age. Robust evidence suggests that disruptions in circadian rhythms, such as those caused by shift work or jet lag, are linked to poorer health outcomes. A recent study found that older adults with more regular daily activity patterns had better cardiorespiratory fitness and walked more efficiently than those with inconsistent routines.
Researchers analyzed data from nearly 800 older adults (average age 76) who wore wrist devices that continuously monitored their movement. They measured how active each person was during the day compared to nighttime rest, identified the time of day when each person was most active, and determined the consistency of these patterns from day to day. The researchers then examined how activity rhythms were related to peak oxygen uptake (a measure of cardiorespiratory fitness) and the energy required to walk at different speeds, while accounting for factors such as age, sex, race, height, and chronic health conditions.
Older adults who showed the greatest difference between daytime activity and nighttime rest had up to 20% better cardiorespiratory fitness and increased walking efficiency. Earlier times of peak activity were also associated with improved outcomes. Additionally, those who reached their peak activity at the same time each day tended to perform more effectively. These patterns encompassed all types of daily movement—including walking, cleaning, gardening, and shopping—not just formal exercise.
These findings suggest that consistent, rhythmic activity patterns play a crucial role in maintaining physical function and health as we age. Learn more about developing an early circadian pattern in this clip featuring Dr. Satchin Panda.
Dietary choices affect not only physical health but also mental well-being. While many studies link healthy eating patterns to lower rates of depression, most focus on idealized diets and overlook the various ways people alter their eating habits in everyday life. A recent study found that restrictive diets may increase depressive symptoms, especially in men or those with a higher body mass index.
Researchers examined data from more than 28,000 adults participating in the National Health and Nutrition Examination Survey who shared details about their diets and moods. They used statistical techniques to explore how different types of diets—such as low-calorie or low-nutrient diets—were associated with mood and whether these connections differed based on a person’s biological sex or body mass index.
Adults who followed calorie-restricted diets reported slightly higher depression scores than those not on any specific diet. Among people with overweight, low-calorie diets were associated with a modest increase in depressive symptoms, while low-nutrient diets were linked to an even greater increase. Men on any diet experienced more physical symptoms of depression, such as low energy or sleep changes. Men following nutrient-restrictive diets also reported more issues like sadness and trouble concentrating than women who weren’t dieting.
These findings suggest that restrictive diets may take a mental toll, especially for men and people with overweight. One well-studied strategy for losing weight and improving mood is intermittent fasting. Learn more about intermittent fasting in this episode featuring Dr. Mark Mattson.
Aging compromises muscle strength and bone density, altering the signaling pathways that coordinate their function. These pathways involve myokines—hormone-like proteins released by muscle during exercise that help regulate metabolism, enhance muscle performance, and support bone formation. A recent study found that levels of a myokine called cardiotrophin-like cytokine factor 1 decline sharply with age but rise by nearly 70% following resistance exercise in both humans and mice.
Researchers measured cardiotrophin-like cytokine factor 1 levels in muscle and blood samples from young and older adults before and after single and long-term resistance training sessions. In younger participants, a single session triggered a sharp rise in cardiotrophin-like cytokine factor 1 levels. In older adults, however, levels only increased after 12 weeks of consistent training. The researchers linked this diminished response to a decline in cytokine receptor-like factor 1, a companion protein required for the myokine’s release.
Then they restored cardiotrophin-like cytokine factor 1 levels in older mice and found that muscle strength, glucose tolerance, and mitochondrial activity improved. Bone density also increased as the myokine reduced bone-resorbing cells and boosted bone-forming cells. Blocking the myokine prevented these exercise benefits, confirming its essential role in maintaining musculoskeletal health.
These findings suggest that aging limits the body’s ability to produce key exercise-related proteins, potentially explaining why older adults respond more slowly to training. However, regular training counters these effects. Dietary protein intake influences the body’s response to training, too. Learn more in this clip featuring Dr. Stuart Phillips.
