Gene Eating

1. Genes Predispose, Environment Triggers: The Obesity Equation

The reason we have become more obese as a species is because we eat too much and don’t move enough.

Nature and Nurture. While genes significantly influence our predisposition to gain weight, the modern "obesogenic" environment—characterized by readily available, calorie-dense foods and sedentary lifestyles—acts as the primary trigger for the obesity epidemic. Genes determine how efficiently we store and utilize energy, but the environment dictates whether those genes are advantageous or detrimental.

Twin Studies and Ethnic Groups. Studies on twins raised apart demonstrate the strong heritability of body weight, approximately 70%. Certain ethnic groups, like the Pima Indians and Polynesian Pacific Islanders, exhibit a higher susceptibility to obesity due to millennia of adaptation to fluctuating food availability, which now clashes with the constant "feast" of the modern world.

Evolutionary Mismatch. Our bodies are evolved to crave energy-dense foods and conserve energy, preparing for famines that rarely arrive. This evolutionary mismatch, combined with genetic predispositions, explains why some individuals struggle more than others to maintain a healthy weight in the current environment.

2. The Brain: The Command Center for Hunger and Satiety

More than almost anything however, your brain absolutely hates it when you lose any weight.

Hormonal Signals. The brain, particularly the hypothalamus, integrates long-term signals from fat (like leptin) and short-term signals from the gut to regulate food intake and energy expenditure. Leptin, often misunderstood as a satiety signal, functions primarily as a starvation hormone, triggering a cascade of responses to conserve energy and increase hunger when fat stores are low.

The Melanocortin Pathway. This pathway, involving POMC neurons and the MC4R receptor, plays a crucial role in appetite control. Mutations in genes within this pathway, such as POMC and MC4R, can lead to hyperphagia (overeating) and severe obesity, as seen in both humans and animals like Labrador retrievers.

Genetic Variation. Genome-wide association studies (GWAS) have revealed that genes influencing body mass index (BMI) are primarily expressed in the brain, while genes affecting waist-to-hip ratio (WHR) are mainly expressed in fat tissue. This suggests that where we store fat is genetically distinct from how much fat we carry.

3. Calories: Equal in Physics, Unequal in Physiology

All calories are equal, but some are more equal than others.

Caloric Availability. While a calorie is a standard unit of energy, the actual amount of energy our bodies extract from food varies depending on factors like food processing, cooking methods, and individual digestive efficiency. For example, cooked chicken provides more available calories than raw chicken, and processed corn tortillas yield more energy than whole sweetcorn kernels.

Macronutrient Digestion. The energy cost of digesting different macronutrients also varies. Protein requires the most energy to break down (around 30% of consumed calories), followed by carbohydrates (5-10%), while fat is the most efficiently digested (around 3%).

Meal Timing. Emerging evidence suggests that the timing of calorie consumption can influence weight management. Eating a larger proportion of calories earlier in the day may be more beneficial for weight loss than consuming a large evening meal, aligning with the body's natural circadian rhythms.

4. Paleo Diet: A Romanticized, Oversimplified Ancestral Tale

There are very few chronic illnesses or diseases that do not respond favorably to our ancestral diet, the diet to which our species is genetically adapted.

The Paleo Promise. The Paleo diet, based on the presumed eating habits of Paleolithic humans, advocates for lean meats, seafood, fruits, and non-starchy vegetables while excluding grains, legumes, dairy, and processed foods. Proponents claim this diet aligns with our genetic makeup and can prevent or reverse chronic diseases.

Hunter-Gatherer Diversity. Archaeological evidence suggests that Paleolithic diets varied widely depending on geographic location and available resources. There was no single "ancestral diet," and humans have adapted to a broad range of energy substrates.

Modern Food Transformation. The foods we consume today have been significantly altered through millennia of agriculture and selective breeding. Modern fruits, vegetables, and meats bear little resemblance to their Paleolithic counterparts, rendering the Paleo diet an idealized, unattainable goal.

5. Gluten: The Good, the Bad, and the Marketing Hype

Obese people are not morally bereft, lazy or bad. They are fighting their biology.

Gluten's Role. Gluten, a protein found in wheat, barley, and rye, provides elasticity and structure to baked goods. While essential for many culinary creations, gluten can trigger adverse reactions in individuals with coeliac disease and non-coeliac gluten sensitivity.

Coeliac Disease. This autoimmune disorder, affecting 1-2% of the population, is triggered by gluten ingestion, leading to damage in the small intestine. The only treatment for coeliac disease is a strict, lifelong gluten-free diet.

Non-Coeliac Gluten Sensitivity. A less well-defined condition, non-coeliac gluten sensitivity involves symptoms similar to IBS that improve with gluten removal. However, the lack of specific biomarkers makes diagnosis challenging, and many self-diagnose based on anecdotal evidence.

6. Detoxification: A Liver's Job, Not a Juice's Claim

Disease is the body in preservation mode straining to maintain the homeostasis of its internal, alkaline fluids.

The Detox Myth. "Detox" diets and cleanses claim to eliminate accumulated toxins from the body, promising improved health, energy, and weight loss. However, these claims are largely unsubstantiated by scientific evidence.

The Liver's Role. The liver is the body's primary detoxification organ, constantly filtering blood, metabolizing nutrients, and eliminating waste products. A healthy liver efficiently performs these functions without the need for special diets or supplements.

Potential Harm. While some components of detox diets, like fruits and vegetables, are beneficial, others, such as extreme calorie restriction or excessive consumption of certain substances, can be harmful and may even impair liver function.

7. Plant-Based vs. Vegan: A Matter of Health, Ethics, and Semantics

I am ‘plant-based’, NOT a vegan.

Divergent Motivations. While both plant-based and vegan diets emphasize plant-derived foods, their underlying motivations differ. Veganism is primarily driven by ethical concerns about animal welfare, while plant-based diets often focus on health benefits.

Dietary Restrictions. Plant-based diets, particularly those inspired by figures like Colin Campbell, often prioritize whole, unprocessed plant foods, limiting or excluding refined sugars, oils, and processed vegan products. Vegan diets, while excluding all animal products, may be more lenient regarding processed foods.

The Spectrum of Beliefs. The plant-based community encompasses a range of beliefs, from those who view it as a way to optimize health to those who see it as a moral imperative. This diversity can lead to disagreements and even hostility within the community.

8. The Allure and Peril of the "Eat Like Me" Culture

Eat like this and look like me.

Social Media Influence. Social media platforms, particularly Instagram, have amplified the "eat like me" culture, where influencers promote specific diets and lifestyles as pathways to health, beauty, and success. This can create unrealistic expectations and contribute to body image issues.

The Dark Side of Wellness. The pursuit of "wellness" can become obsessive and even harmful, leading to disordered eating patterns like orthorexia. The moralization of food and the pressure to achieve an idealized body can create anxiety and self-blame.

The Power of Anecdotes. Testimonials and personal stories often carry more weight than scientific evidence in the "eat like me" culture. While anecdotes can be inspiring, they should not be used as a substitute for evidence-based information.

9. The Mediterranean Diet: A Sustainable Path to Health

The human body in its perfect state of health is alkaline in its design.

A Traditional Approach. The Mediterranean diet, based on the eating habits of people living around the Mediterranean Sea, emphasizes olive oil, fruits, vegetables, whole grains, legumes, nuts, and fish, with limited red meat and dairy.

Proven Benefits. Numerous studies, including the PREDIMED trial, have demonstrated the health benefits of the Mediterranean diet, including reduced risk of cardiovascular disease, type 2 diabetes, and certain cancers.

Sustainable and Enjoyable. Unlike restrictive fad diets, the Mediterranean diet is a balanced, sustainable, and enjoyable way of eating that can be adapted to individual preferences and cultural contexts.

10. Personalized Nutrition: A Distant Promise, Not a Current Reality

You find out that life is just a game of inches.

The Promise of Nutrigenomics. The idea of tailoring diets to individual genetic profiles holds great promise for optimizing health and preventing disease. However, current genetic tests offer limited predictive power due to the complexity of gene-environment interactions.

Limitations of Genetic Testing. Most genetic tests only analyze a small fraction of known genetic variations and struggle to accurately measure environmental factors like diet and physical activity. This makes it difficult to provide truly personalized dietary recommendations.

Focus on Fundamentals. While personalized nutrition may become a reality in the future, the best approach for most people is to focus on evidence-based dietary principles, such as eating a variety of whole foods, limiting processed foods, and maintaining a healthy weight.

Last updated: April 1, 2025