Postprandial triglycerides in response to high fat: role of dietary carbohydrate

Effects of Ketogenic Dieting on Body Composition, Strength, Power, and Hormonal Profiles in Resistance Training Men

Wilson, JM, Lowery, RP, Roberts, MD, Sharp, MH, Joy, JM, Shields, KA, Partl, JM, Volek, JS, and D'Agostino, DP. Effects of ketogenic dieting on body composition, strength, power, and hormonal profiles in resistance training men. J Strength Cond Res 34(12): 3463-3474, 2020-This study investigated the impact of an isocaloric and isonitrogenous ketogenic diet (KD) versus a traditional western diet (WD) on changes in body composition, performance, blood lipids, and hormonal profiles in resistance-trained athletes. Twenty-five college-aged men were divided into a KD or traditional WD from weeks 1 to 10, with a reintroduction of carbohydrates from weeks 10 to 11, while participating in a resistance training program. Body composition, strength, power, and blood lipid profiles were determined at weeks 0, 10, and 11. A comprehensive metabolic panel and testosterone levels were also measured at weeks 0 and 11. Lean body mass (LBM) increased in both the KD and WD groups (2.4% and 4.4%, p < 0.01) at week 10. However, only the KD group showed an increase in LBM between weeks 10 and 11 (4.8%, p < 0.0001). Finally, fat mass decreased in both the KD (-2.2 ± 1.2 kg) and WD groups (-1.5 ± 1.6 kg). Strength and power increased to the same extent in the WD and KD conditions from weeks 1 to 11. No changes in any serum lipid measures occurred from weeks 1 to 10; however, a rapid reintroduction of carbohydrate from weeks 10 to 11 raised plasma triglyceride levels in the KD group. Total testosterone increased significantly from weeks 0 to 11 in the KD diet (118 ng·dl) as compared to the WD (-36 ng·dl) from pre to post while insulin did not change. The KD can be used in combination with resistance training to cause favorable changes in body composition, performance, and hormonal profiles in resistance-trained men.

Low carbohydrate diets in family practice: what can we learn from an internet-based support group

The Active Low-Carber Forums (ALCF) is an on-line support group started in 2000 which currently has more than 86,000 members. Data collected from posts to the forum and from an on-line survey were used to determine the behavior and attitudes of people on low carbohydrate diets. Members were asked to complete a voluntary 27-item questionnaire over the internet. Our major findings are as follows: survey respondents, like the membership at large, were mostly women and mostly significantly overweight, a significant number intending to and, in many cases, succeeding at losing more than 100 lbs. The great majority of members of ALCF identify themselves as following the Atkins diet or some variation of it. Although individual posts on the forum and in the narrative part of our survey are critical of professional help, we found that more than half of respondents saw a physician before or during dieting and, of those who did, about half received support from the physician. Another 28 % found the physician initially neutral but supportive after positive results were produced. Using the same criteria as the National Weight Registry (without follow-up)--30 lbs or more lost and maintained for more than one year--it was found that more than 1400 people had successfully used low carb methods. In terms of food consumed, the perception of more than half of respondents were that they ate less than before the diet and whereas high protein, high fat sources replaced carbohydrate to some extent, the major change indicated by survey-takers is a large increase in green vegetables and a large decrease in fruit intake. Government or health agencies were not sources of information for dieters in this group and a collection of narrative comments indicates a high level of satisfaction, indeed enthusiasm for low carbohydrate dieting. The results provide both a tabulation of the perceived behavior of a significant number of dieters using low carbohydrate strategies as well as a collection of narratives that provide a human perspective on what it is like to be on such a diet. An important conclusion for the family physician is that it becomes possible to identify a diet that is used by many people where the primary principle is replacement of starch and sugar-containing foods with non-starchy vegetables, with little addition of fat or protein. Used by many people who identify themselves as being on the Atkins diet, such a strategy provides the advantages of carbohydrate-restricted diets but is less iconoclastic than the popular perception and therefore more acceptable to traditional nutritionists. It is reasonable for family practitioners to turn this observation into a recommendation for patients for weight control and other health problems.