Calories Count: Gut Microbes and Leftovers Matter

Ruminating on Appetite and Digestion

The concept of “calories in, calories out” is often simplified to mean that weight change is solely determined by the balance between the calories you consume and the calories you expend. However, recent research suggests that there’s more to it. Biologically active leftover components of food, known as bioactives, play a significant role in regulating your body’s metabolic control centers, including your brain’s appetite center, gut’s digestive bioreactor, and cells’ metabolic powerhouses.

Fiber and polyphenols, for instance, help regulate your appetite and calorie intake by transforming into metabolites that naturally decrease your appetite. These metabolites also regulate the same gut hormones that control appetite, making whole foods with bioactives a crucial component of a healthy diet.

On the other hand, processed foods lack bioactives and are often formulated with salt, sugar, fat, and additives to be hyperpalatable, causing you to crave them and eat more.

Mitochondrial Maestros in the Middle

A full accounting of calories also depends on how effectively your body burns them to power your movement, thoughts, immunity, and other functions – a process largely orchestrated by your mitochondria. Healthy people typically have high-capacity mitochondria that easily process calories to fuel cellular functions, while those with metabolic diseases have mitochondria that don’t work as well, contributing to bigger appetites, less muscle, and increased fat storage.

Mitochondria also have less of a mitochondria-rich type of fat called brown fat, which burns calories to produce heat. Less brown fat might explain why some people with obesity can have lower body temperatures than those who aren’t obese.

Please Mind the Microbiome Gap

A healthy microbiome produces a full range of beneficial metabolites that support calorie-burning brown fat, muscle endurance, and metabolic health. However, not everyone has a microbiome capable of converting bioactives into their active metabolites.

Long-term consumption of processed foods, low in bioactives and high in salt and additives, can impair the microbiome’s ability to produce the metabolites needed for optimal mitochondrial health. Overuse of antibiotics, high stress, and lack of exercise can also adversely affect microbiome and mitochondrial health.

This creates a double nutrition gap: a lack of healthy diet and a deficiency in the microbes to convert its bioactives. As a result, well-studied nutritional approaches such as the Mediterranean diet might be less effective in some people with an impaired microbiome, potentially leading to gastrointestinal symptoms such as diarrhea and negatively affecting metabolic health.

Tools to Transform Fat into Fuel

For most people, restoring the microbiome through traditional diets such as the Mediterranean diet remains biologically achievable, but it is not always practical due to challenges such as time, cost, and taste preferences. In the end, maintaining metabolic health comes back to the deceptively simple healthy lifestyle pillars of exercise, sleep, stress management, and nutritious diet.

Some simple tips and tools can nonetheless help make nutritious diet choices easier. Mnemonics such as the 4 F’s of food – fibers, polyphenols, unsaturated fats, and ferments – can help you focus on foods that best support your microbiome and mitochondria with “leftovers.” Bioactive-powered calculators and apps can also aid in selecting foods to control your appetite, digestion, and metabolism to rebalance your calorie “ins and outs.”

Conclusion

In conclusion, while the concept of “calories in, calories out” is accurate, it’s essential to consider the role of bioactives, mitochondria, and the microbiome in determining your body’s metabolic health. By focusing on whole foods with bioactives, maintaining a healthy microbiome, and adopting a balanced lifestyle, you can optimize your metabolic health and achieve your weight loss goals.

FAQs

Q: What are bioactives, and why are they important?
A: Bioactives are biologically active leftover components of food that play a significant role in regulating your body’s metabolic control centers.

Q: How do bioactives affect appetite and digestion?
A: Bioactives help regulate appetite and calorie intake by transforming into metabolites that naturally decrease appetite and regulate gut hormones.

Q: What is the role of mitochondria in metabolism?
A: Mitochondria are responsible for processing calories to fuel cellular functions. Healthy people typically have high-capacity mitochondria that easily process calories, while those with metabolic diseases have mitochondria that don’t work as well.

Q: What is the relationship between the microbiome and metabolism?
A: A healthy microbiome produces beneficial metabolites that support calorie-burning brown fat, muscle endurance, and metabolic health. However, an impaired microbiome can lead to gastrointestinal symptoms and negatively affect metabolic health.

Q: How can I optimize my metabolic health?
A: Focus on whole foods with bioactives, maintain a healthy microbiome, and adopt a balanced lifestyle that includes regular exercise, sufficient sleep, stress management, and a nutritious diet.