In this article we explain the basis for a successful diet.

<  Previous: Basic Principles of Nutrition Part I

I will start this article with references to scientific research and analysis. But stay with me until the end. I promise that not only will I be as brief as I can be, but what you read will help you lose the extra pounds.

So let's start with a survey conducted in 2007: Gardner CD, Kiazand A, Alhassan S, et al. Comparison of the Atkins, Zone, Ornish, and LEARN diets for change in weight and related risk factors among overweight premenopausal women: the A TO Z Weight Loss Study: a randomized trial. JAMA. 2007;297(9):969-977. doi:10.1001/jama.297.9.969

311 overweight and obese women aged 25-50. Each of them was placed in 1 of the following 4 diet groups:

• Atkins (extremely low carbohydrate) -> 4.7kg weight loss in 12 months
• Zone diet (relatively low in carbohydrates, relatively high in protein) -> 1.6kg weight loss in 12 months
• LEARN (low in dietary fat) -> 2.2kg weight loss in 12 months
• Ornish diet (extremely high carbohydrate) -> 2.6kg weight loss in 12 months

The big difference between Atkins and the zone diet has got scientists thinking in an attempt to clarify the reason for it.

They felt that the insulin resistance may play a role, but the relevant survey in 2016 (Gardner CD, Offringa LC, Hartle JC, Kapphahn K, Cherin R. Weight loss on low-fat vs. low-carbohydrate diets by insulin resistance status among overweight adults and adults with obesity: a randomized pilot trial. obesity (Silver Spring). 2016 Jan;24(1):79-86. doi: 10.1002/oby.21331. epub 2015 Dec 6.) showed that this theory is not in the right direction.

Another theory was that there might be a genetic predisposition. One person might be able to lose more weight on a low-fat diet, another on a low-carbohydrate diet, while another might be able to lose weight regardless. So, looking for specific genotypes, the DIETFITS research began. Gardner CD, Trepanowski JF, Del Gobbo LC, et al. Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults and the Association With Genotype Pattern or Insulin Secretion: the DIETFITS Randomized Clinical Trial. JAMA. 2018;319(7):667-679. doi:10.1001/jama.2018.0245.

To make a long story short, this survey was a bust too. Not only did they find no relationship between the specific genotypes they thought might affect weight loss, but the effects of a low-fat diet and a low-carbohydrate diet were similar.

From all of these long-term studies, however, there were commonalities among the people who lost the most weight. These had nothing to do with genotypes, insulin, or type of diet.

These people:

• Did not have high external psychological pressure and/or stress problems
• They didn't eat in a hurry and casually, for example, neither in front of the TV, nor in the car
• They ate home-cooked food, at the table, with their family, talking and without haste
• They ate with the understanding that this would be a long-term thing. In short, if what they ate didn't satisfy them, they would replace it with something they considered more filling.
• And of course because of the research guidelines they minimized foods with added sugars and refined grains

So this is the basis for a successful diet.

Next: Basic Principles of Nutrition Part III - successful dieting needs realism  >