Studies show that the high fat, low fibre, palatable, salty and sugary foods in the Western diet increase energy consumption. The reason for this is that many processed foods bypass the normal appetite regulatory mechanisms and elicit larger food intakes. Because these foods are of low quality and often contain metabolic poisons such as fructose and trans fatty acids, they cause metabolic dysfunction including insulin resistance, the latter being a primary driver of weight gain and obesity (not the actual energy intake). In animal studies. Western foods high in fat and sugar have been shown to have drug like effects including stimulation of the same neuronal pathways associated with the use of drugs such as cocaine. Traditional foods that do not contain high amounts of salt, sugar and fats do not cause these same effects, and so are not addictive in the same way as Western alternatives. In addition, when variety is introduced to a Western buffet or a Western style diet, energy intake can increase by around 25 %.
Bland foods cause weight loss because firstly they allow the normal appetite regulatory mechanisms to function and this prevents overeating. In addition, bland foods are usually whole plant foods and such foods are not obesogenic in nature because they do not contain metabolic poisons and retain their original fibre. However, genetics studies have shown that some individuals might be more susceptible to dietary variety than others on account of the presence of a particular genotype that confers increased responsiveness to tasty food. Research shows that women who are non-tasters of the bitter taste marker 6-n-propylthiouracil have an increased energy intake from a mixed buffet lunch, when compared to women with a genotype that makes them sensitive to 6-n-propylthiouracil. This may suggest that certain individuals find particular tastes unpalatable and that this inhibits their eating behaviour somewhat, while others consume a wider range of foods including those with bitter dressings and sauces as well as those with more fat.
For example, the energy and fat intake of a group of lean healthy women has been tested in a clinical setting using a buffet style ad libitum observational study1. Women were genetically tested and divided into non-taters, medium tasters or supertasters for the bitter taste marker 6-n-propylthiouracil. They were then provided with a buffet lunch or a control meal following a normal breakfast, and their energy and fat intake recorded by the researchers. The results of the study showed that the non-tasters and medium tasters consumed both more energy and more fat than the super tasters at the buffet lunch. When the energy intakes of the women were calculated it was found that the higher intake of energy at the buffet lunch caused a significant increase in the daily energy consumption of the non-tasters (49 kcal per day) and the medium tasters (48 kcal per day) compared to the super tasters. At the buffet lunch the non-tasters and the medium tasters consumed 246 kcals more than during the normal control meal.
Dr Robert Barrington’s Nutritional Recommendation: This study would tend to suggest that polymorphisms within genes may influence feeding behaviour. Interestingly the non-tasters and the medium tasters consumed more fat, more sweets and more energy from snacks across all the study days compared to the super tasters. As these sorts of low quality foods are drivers of obesity, it could be that differences in the phenotypic expression of taste result in changes to not only energy intake, but also the sort of foods eaten. However, while this is interesting from a physiological perspective, there was no forced feeding of foods during this study. The subjects still willingly placed these fat laden, sweet foods in their mouths of their own choice. Free will is a wonderful thing because it allows choices to be made that reflect the personal responsibility of the individual. Eating high quality foods that prevent weight gain and improve health is a free choice available to most and those who chose to take an alternative path must accept the responsibility of their actions.
RdB
