Caloric restriction (average 12.5% over two years) in healthy, non-obese individuals significantly improved all cardiovascular and cardiometabolic risk factors, effectively “gaining 10 years in two years” by Framingham Index. Consider caloric restriction for significant improvements in cardiometabolic health.
Caloric restriction increased mitochondrial biogenesis and reduced reactive oxygen species (ROS) production, suggesting improved mitochondrial function and reduced oxidative stress. Consider caloric restriction for improving mitochondrial function and reducing oxidative stress.
Caloric restriction significantly improved chronic inflammation markers (e.g., CRP, interleukins, TNF-alpha) and reduced fat in the thymus, indicating improved immune function. Consider caloric restriction to reduce chronic inflammation and improve immune health.
Acknowledge that “one size does not fit all” for diet and health, and different strategies and restrictions are needed for groups of people. Seek personalized nutrition strategies rather than universal dietary guidelines.
Accept that living in an “infinite food environment” requires some form of restriction (macronutrients, alcohol, eating window, or direct calories) for weight balance. Identify and implement a sustainable form of dietary restriction.
A nutritional approach to weight loss without prescribed physical activity or exercise is not a good strategy; both should be implemented. Combine nutritional approaches with physical activity for weight loss.
Exercise is an incredibly potent driver of autophagy, a cellular process that cleans out damaged cells and is also fueled by caloric restriction. Engage in regular exercise to promote autophagy and cellular health.
Vigorous exercise can be anorectic (reduces appetite), possibly driven by lactate. Consider vigorous exercise to temporarily reduce appetite.
Be mindful of eating speed after exercise, as eating too quickly can abrogate the energy effect of exercise. Eat slowly after exercise to better regulate intake.
The speed of food delivery to the stomach is important for the kinetics of gut hormones (GLP-1, GIP, CCK, PY-1, Glucagon) which regulate food intake. Eat slowly to optimize gut hormone regulation of intake.
The protein leverage theory suggests people eat for a given amount of protein; if protein density in food decreases, people might increase caloric intake to get sufficient protein. Ensure sufficient protein intake to potentially regulate overall caloric intake.
A ketogenic diet (less than 10% carbohydrate) can lead to a slight, statistically significant increase in sleeping metabolic rate and 24-hour energy expenditure (around 100 calories/day) in the early weeks. It may also have a slight advantage for weight loss during the weight loss period compared to a low-fat diet.
Sustained caloric restriction is “totally manageable” for most people after about one month, especially when increasing food volume and decreasing fat content to maintain satiety. If attempting caloric restriction, understand that initial hunger subsides, and focus on high-volume, low-calorie-density foods.
GLP-1 agonists are potent modulators of food intake and lead to significant weight loss and metabolic health improvements. Discuss GLP-1 agonists with a healthcare professional for weight management and metabolic health.
Physical activity is key for weight loss maintenance, as shown by the weight registry, where successful maintainers engaged in more physical activity. Incorporate physical activity for weight loss maintenance.
Exercise alone is “pretty bad for weight loss” and is a “B minus at best” in terms of evidence for its role in weight loss. Adjust expectations for exercise as a primary weight loss tool.
Understand that individuals have varying metabolisms, meaning some may need to be very restrictive, others moderately mindful, and some less restrictive to maintain weight balance. Assess personal metabolic needs and adjust dietary mindfulness/restriction accordingly.
Building a strong relationship with investigators/coordinators, sharing results, and fostering a community among participants were key to exceptional adherence and retention in a two-year caloric restriction study. When undertaking significant lifestyle changes, seek strong support systems, track progress, and engage with a supportive community.
Many participants in the CALERIE study maintained some weight loss and continued to use learned strategies more than 15 years after the study, indicating lasting lifestyle changes. View participation in structured health interventions as an opportunity for long-term lifestyle change and learning.
Caloric restriction leads to metabolic adaptation, making the body more efficient (burning less energy than expected for body weight). Be aware that caloric restriction can lead to increased metabolic efficiency, which might make further weight loss harder but could be beneficial for longevity.
Better public education and advocacy from scientific/medical communities are needed to help people understand that they are not “broken” if average approaches don’t work, and to empower them to find personalized solutions. Seek out better education and advocacy on personalized nutrition.
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