I visited sciencedaily.com yesterday to see what was the latest on diet and exercise, and, unsurprisingly, there was a research study done on rodents that found a low carbohydrate-high fat diet produced more weight, and especially fat weight on overweight and pre-diabetic mice coupled with worsened glucose tolerance and higher insulin levels. This was in contrast to the control group that ate their normal diet. The researcher made the bold statement from this project that the “Paleo” diet, which is very low carbohydrate and high fat, should be avoided, especially by individuals that are overweight and sedentary. Furthermore, he claimed that there was no research touting the benefits of a low carb or paleo diet.
Of you are curious about the study, here is the link. Paleo Diet is Dangerous.
Wow. That is a bold claim. Most researchers, when confronted with the results of a study, use the phrase “may lead to”, “suggests that”, or the most common statement is “further research is necessary”, meaning the researcher finds the study uncovered some data that is intriguing and may be beneficial to implement, but not as an absolute truth that must be adhered to by the population at large. It sounds to me like this researcher has an agenda against the low carb-high fat diet that is gaining traction. I am a bit skeptical of his findings, but I always something of value, even from viewpoints I disagree with or research that do not seem to make sense. With that in mind, let us take a closer look at the study and see what we can really learn from it.
The researchers took a group of mice that were six weeks old and, up to that point, fed a normal rat chow diet. They then divided the mice into two different groups. One group, the control group, was fed the normal rat chow which consisted of a macro-nutrient breakdown as such: 70% carbohydrate, 20% protein, and 10% fat. The macro-nutrient content of the second group was made up of 6% carbohydrate, 13% protein, and 81% fat. Moreover, the fat breakdown of the second group was 55% saturated, 37% mono saturated, and 8% polyunsaturated fat. This is important in my view because I do recommend that my clients eat a higher portion of saturated fat than polyunsaturated fat, and the main reason I recommend it is because too many polyunsaturated fats can throw off the balance between Omega 3 and Omega 6 fatty acids in the body. An overabundance of Omega 6 fatty acids tend to accelerate the aging process, and polyunsaturated fats are loaded with Omega 6 fatty acids. They let the mice eat ad libitum , basically meaning the mice could eat all they want without restriction on both diets for another 9 weeks. Body weight, body fat, blood glucose, triglyceride, and cholesterol levels were tested throughout the study, and ß-cell mass was measured after the conclusion of the study. Healthy ß-cell function is important for the pancreas to produce insulin in response to glucose in the bloodstream.
The low carbohydrate-high fat diet did improve the blood profile in that plasma triglycerides decreased, and HDL and total cholesterol went up. The researcher on this project believes that higher total cholesterol is not good, although many other researchers believe otherwise. Higher HDL concentrations in the blood is good because it is the HDL’s that bring the LDL’s back to the liver to be reprocessed. It is an abundance of LDL’s in the bloodstream that lead to increased risk of heart disease.
However, the mice fed a low carbohydrate diet gained more weight than the mice fed the regular rat diet, but then again, the mice on the regular chow gained weight as well, just not as much. The researchers did not determine if there was a change in muscle mass (this would have been good to know). The low carbohydrate diet also did not improve insulin secretion or ß-cell mass.
The reason that this researcher believes that the low carb diet, based on these results, is not good for people with metabolic syndrome or diabetes is that it is easy to gain weight, and especially fat weight on a low carb diet, and that the low carb diet does not improve insulin sensitivity.
Even thought the researcher came to a conclusion I do not agree with, I do believe that this was a good study. The main answer the researcher was looking for from the study was this: can a low carbohydrate diet improve ß-cell function, and can it aid in the regeneration of ß-cells? ß-cells in the pancreas produce insulin that helps shuttle glucose out of the bloodstream, so a well functioning pancreas can keep diabetes at bay. He found that a low carbohydrate diet, at least in mice, does not do that.
However, I am surprised that the mice fed a low carbohydrate diet gained fat. More often than not, a low carbohydrate diet tends prevent overeating for a number of reasons, thus making it easier to stay lean, even though one eats more overall fat than on a high carbohydrate diet. This study claims otherwise, but then again, this is only one study.
This study did not impress upon me the need to avoid using a low carb or Paleo diet for fat loss, or for that matter better overall health, for I disagree with the researcher that there are no studies proving the health benefits of a low carb-high fat diet. The Inuit, for example, have for many generations lived on a very very low carbohydrate diet simply because they had no access to any kind of carbs. They ate basically protein and fat, and they had no problem with obesity, heart disease and diabetes. Furthermore, doctors, as far back as the 1800’s, would often recommend to their clients who needed to lose excess fat to cut back on carbohydrate intake….not fat intake. Through years of observation, they found a low carb diet to work. This is just the tip of the iceberg, so to speak. There are more and more studies proving the efficacy of the Paleo way of eating.
I am taking this study with a grain of salt, for there needs to be more research proving his hypothesis to sway me to change my position stand.