Some are touting the keto diet as a wellness lifestyle, but does the nutritional and physiological impact make it more of a short-term fix?
There is a never-ending parade of diets that promise all sorts of quick weight-loss results as part of a wellness lifestyle. They become popular and then fade away so quickly that it becomes hard to remember which one made the list of Top 10 Hottest Summer Diets for last year.
Part of the reason for this is due to the fact that these diets may promise fast results, but are invariably unable to deliver them. A large part of the reason for their failure is that weight loss often depends upon some sort of meal replacement, such as bars or shakes, which do not taste appealing. Human nature being what it is, sticking with a diet that involves eating something unappealing is doomed to failure.
On the other hand, diets that emphasize fresh, unprocessed food tend to be more attractive, so are often more successful. The key to such diets is not in replacing normal food, but in changing how people eat, making the body more efficient at caloric intake and burn.
The keto (or ketogenic) diet is one of the most popular of these diets because it focuses on making fat burning more effective while still eating healthy food. Despite its popularity, there is some caution regarding long-term use as a wellness lifestyle. How does the keto diet work, and is it better over the short term or as a change in lifestyle?
How keto works
The keto diet works by reducing carbs to less than 10% of total daily intake in favor of fresh fruits and vegetables (on a limited basis) and lean meats.1
Eliminating carbs/glucose requires the body to find another fuel source, so it will instead draw on fat. The liver turns this fat into ketones, which serve as this alternate fuel source. The keto diet makes up for the reduced carb intake by increasing fats to approximately 70-90% of a 2,000 calorie per day diet.1,2
Weight-loss results
Several small studies have shown positive results with the keto diet. A 2013 meta-analysis pooled together several such studies to look for a pattern of similarity among the findings in an effort to strengthen the overall results.3
The combined results showed that the people who followed a keto diet lost an average of two pounds more than those who followed just a low-fat diet over the course of one year. A similar meta-analysis study from 2016 found that people who followed the keto diet lost five pounds more than those on a low-fat diet for six months.4
Will keto work over the long term as a wellness lifestyle?
While the two meta-analyses look promising, other research is cautious as to the effectiveness of the keto diet for long-term weight loss — or health in terms of eating a high-fat diet all the time. A 2018 meta-analysis also found that the keto diet showed moderate weight loss improvement over a low-fat diet for periods up to one year.5
However, these studies also showed a dropout rate between 13-84%. Furthermore, the weight loss was not sustained for an extended length of time. The researchers concluded:
Ketogenic diets can help patients lose about 2 kg more than low-fat diets do at one year, but higher-quality studies show no difference. Weight loss peaks at about five months but is often not sustained.5
There does seem to be solid evidence that the keto diet does work better than standard low-fat diets for weight loss over the short term, up to one year. However, it may not continue to be as effective as a long-term wellness lifestyle. The best compromise when talking to your patients about nutrition may be a less restrictive diet after the initial weight loss on the keto diet.
References
- Masood W, Uppaluri KR. Ketogenic diet. [Updated 2020 Feb. 18]. In: StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing.
- Shilpa J, Mohan V. Ketogenic diets: Boon or bane? Indian Journal of Medical Research. 2018;148(3):251-253.
- Bueno NB, de Melo IS, de Oliveira SL, da Rocha Ataide T. Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials. British Journal of Nutrition. 2013;110(7):1178-1187.
- Mansoor N, Vinknes KJ, Veierød MB, et al. Effects of low-carbohydrate diets v. low-fat diets on body weight and cardiovascular risk factors: A meta-analysis of randomised controlled trials. British Journal of Nutrition. 2016;115(3):466-479.
- Ting R, Dugré N, Allan GM, Lindblad AJ. Ketogenic diet for weight loss. Canadian Family Physician. 2018;64(12):906.