The old school teaching about obesity went like this. Consume more calories than you burn and you gain weight. Consume less calories than you burn and you lose weight. Obesity is just a problem of self control. All calories are the same.

This way of thinking has been dis proven but still pervades many discussions.

Ample evidence supports the following facts that should be considered in choosing foods and mitigating the obesity epidemic.

• High glycemic high carbohydrate foods and beverages such as bread, pasta, potatoes, crackers, chips, granola bars, breakfast cereal, soda, energy drinks produce a rapid rise in blood sugar and insulin levels, stimulate hunger, enhance further carbohydrate cravings, and drive people to overeat. Thus, what kind of food you eat affects how much you eat. (1,2)
• High carbohydrate diets  result in decreased calorie burning (decreased metabolic rate) compared to high fat high protein diets. Thus, a diet with carbohydrate restriction not only limits hunger (improves satiety) but also results in burning more calories for the same level of activity and at rest. I have previously discussed weight loss studies that consistently demonstrate that carbohydrate restriction results in spontaneous reduction in caloric consumption. At the same time this approach results in burning more calories while you watch TV or go for a walk. (3)
• The human body does not absorb all of the calories present in food. A higher % of the calories present in highly processed refined foods (which represent 70% of the American diet) are absorbed compared to whole unprocessed foods such as tree nuts. (4)
• Whole foods, especially non-starchy vegetables, provide much more satiety producing fiber (non-starchy vegetables have five to seven times as much fiber compared to whole grain bread on a per calorie basis)
• Food choices produce different effects on the gut flora. A diet consisting of whole hunter-gatherer type foods (grass fed meat, free range poultry and eggs, wild seafood, fresh fruits, vegetables and nuts) enhance and support the development of “good bacteria” in the gut. As discussed before , the gut flora have a major impact on the risk of obesity and other diseases.
• High carbohydrate diets produce higher insulin levels.  Insulin results in conversion of carbohydrate into fat and storage of fat. Insulin inhibits the burning of fat. Carbohydrate restriction results in burning fat for energy.
• The process of protein digestion consumes more calories compared to the digestion of carbohydrate. Protein has a higher  thermogenic effect compared to carbohydrate.

THE BOTTOM LINE: not all calories are the same. The quality of the food we consume affects our metabolic rate, our absorption of calories, how quickly we feel full and therefore how many calories we consume, and the mix of good bacteria and bad bacteria that live in our GI tract.

Good health, peace and tranquility to all

BOB

1. Fed Up Asks, Are All Calories Equal? – NYTimes.com

2. Changes in diet and lifestyle and long-term wei… [N Engl J Med. 2011] – PubMed – NCBI

3. Effects of Dietary Composition During Weight Loss Maintenance: A Controlled Feeding Study

4. Impact of Peanuts and Tree Nuts on Body Weight and Healthy Weight Loss in Adults