Fasting has gained immense popularity as a dietary approach, but what does the scientific evidence say about its health benefits?

Studies have explored how fasting might influence metabolic markers, energy expenditure, and even aging. However, while fasting shows promise in some animal models, translating these effects to humans is less clear.

A key part of the debate centers on whether fasting offers unique health advantages or whether its benefits stem primarily from reduced calorie intake. Time-restricted eating and intermittent fasting protocols show promise in regulating appetite and reducing energy intake, potentially leading to weight loss. But, when calories are controlled, does fasting still improve health independently?

This episode explores the evidence to determine if fasting confers metabolic advantages over non-fasting diets. In addition, we’ll take a look at its impact on behavioral patterns and ask if that could play a pivotal role in promoting better health outcomes.

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Timestamps:

• [00:54] Defining fasting
• [03:44] Historical context and early research
• [08:01] Mechanisms and claims of fasting
• [18:15] Types of fasting protocols
• [22:18] Time-restricted eating and chronobiology
• [28:29] Energy expenditure and behavioral changes
• [36:53] Fasting vs. weight loss: independent benefits
• [41:47] Health markers and weight loss outcomes
• [43:37] Muscle mass concerns during fasting
• [47:31] Animal models vs. human studies
• [51:29] InterFAST study insights
• [01:00:37] Behavioral vs. metabolic changes
• [01:11:25] So what do we know?

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• Go to the page for this episode

Body image and self-worth are deeply intertwined concepts that influence how we see ourselves and interact with the world. Many people believe that changing their physique is the key to improving their body image, but is it really that simple? This connection between appearance and self-esteem raises important questions about how we define confidence and whether our sense of worth should be tied to how we look.

Our relationship with food plays a crucial role in how we view ourselves. While some see food as fuel, others attach much more significance to their eating habits, often linking dietary choices to discipline, success, or failure. But what happens when these beliefs become too rigid? Understanding how our perceptions of food and body image are shaped is essential for navigating the balance between health, happiness, and personal fulfillment.

Physique change, often seen as a positive goal, can bring about unexpected psychological impacts. Pursuing a leaner or more muscular body might boost temporary feelings of confidence, but could it also reinforce negative patterns of thought?

In an episode co-hosted with Dr. Eric Trexler, Danny talks with Dr. Gabrielle Fundaro in order to tackle some of these concepts and questions.

Timestamps:

• [04:54] Start of conversation
• [06:40] Defining body image and self esteem
• [12:26] Relationship with food and weight controllability beliefs
• [20:38] Impact of body composition on body image
• [27:40] Challenges in changing body image perceptions
• [34:43] Influence of coaches on client body image
• [41:57] Screening for disordered eating
• [51:50] Ethical responsibilities of fitness professionals
• [54:53] Improving body image without physique change
• [61:02] Key ideas segment (premium-only)

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• Join the Sigma email newsletter for free
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• Get more of Dr. Trexler’s research analysis with the MASS Research Review
• Related previous episodes: See episodes 484 and 367

Some suggest that, since individual lifts or short-duration efforts don’t rely heavily on glycogen, carb intake might not be critical for strength athletes. If glycogen depletion isn’t a pressing issue, could athletes thrive on lower-carb diets without sacrificing performance? Or could there be overlooked benefits to having greater carbohydrate availablily in those sessions?

• In strength sports and resistance training, do carbohydrates play an important role or not?
• Are carbohydrates really necessary for resistance training?
• How does training volume, intensity and goals impact the carbohydrate requirement?

In this episode, Dr. Cliff Harvey and Dr. Eric Helms offer their perspectives on this interesting and practically important issue.

Timestamps:

• [00:03:40] Do carbohydrates have a role in resistance training?
• [00:12:23] Do individuals respond differently?
• [00:18:25] Recent research insights
• [00:35:08] Carbohydrate “sensing” and performance
• [00:47:17] How to think about carbohydrate needs
• [00:54:06] Changing views on nutrient timing
• [01:06:37] Ketogenic diets and muscle gain
• [01:22:02] Dietary patterns and health – Are macronutrients that important?
• [01:31:42] Key ideas segment (Premium-only)

Links:

• Subscribe to Premium for study notes and transcript
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• Sports Nutrition Association
• Get more of Dr. Helm’s research analysis with the MASS Research Review
• SigmaNutrition.com