There is perhaps no goal more common in health and wellness circles than weight loss. It seems to be everyone’s New Year’s Resolution. Countless blogs, social media posts, podcasts, and lectures at medical conferences focus on teaching Americans to lose weight.
But how many succeed?
According to The American Journal of Clinical Nutrition, about 20% of people who lose a significant amount of weight are able to keep it off long term, but the AJCN definition of “keeping the weight off” is losing 10% of body weight and maintaining it for one year.
Many people who embark on a weight loss journey are more ambitious. Their goal is to lose weight (often well in excess of 10% of body weight) and keep it off for good.
What is the best way to do this?
Do ketogenic diets work for weight loss?
One of the commonly recommended protocols for those struggling with weight is the ketogenic diet. Ketogenic diets are low in carbohydrates, and high in fat, with the goal of forcing the body to burn fat as fuel rather than glucose. To be sure, some people can and do lose weight on ketogenic diets, but do they keep it off? Furthermore, are ketogenic diets heart healthy?
The answers will vary by individual. Some ketogenic diet studies show promise for weight loss, while others don’t. A 2004 study, which appeared in the Journal of Experimental and Clinical Lipidology, showed benefits in reducing weight and heart health markers, like LDL-C, over 24 weeks when overweight subjects were placed on a ketogenic diet.
What adds to the confusion for consumers is the lack of consistency in the evidence.
For example, this study, which appeared in 2019 in the Journal Atherosclerosis. 30 healthy adults were placed on a high fat ketogenic style diet with less than 20g of carbohydrate per day and had their LDL-C measured after 3 weeks. On average, LDL-C went up by 44%, but the range of increase varied between 5% – 107%.
Clearly, the benefits of losing weight on a ketogenic diet aren’t worth it if the dieter increases his or her risk for heart disease in the process.
However, despite concerns about what keto diets might do to some people’s lipid profiles, many health commentators, dietitians, and physicians recommend keto for weight loss. For example, Dr. David S. Ludwig, writing in The Journal Nutrition, offers the case for ketogenic diets as a tool for fighting obesity, and concludes with a call for more research:
High-quality clinical trials of ketogenic diets will be needed to assess important questions about their long-term effects and full potential in clinical medicine.Dr. David S. Ludwig
Well, one of those high quality clinical trials has arrived and the results suggest that personalized nutrition offers a better, more sustainable approach to weight loss than ketogenic diets.
DNA diets vs. keto for weight loss
Appearing in 2020 in the peer reviewed journal BMC Nutrition, this study titled “A comparison of a ketogenic diet with a LowGI/nutrigenetic diet over 6 months for weight loss and 18-month follow-up,” found that a diet tailored to DNA far outperformed a ketogenic diet for 114 obese subjects at a weight loss clinic.
The study format allowed subjects to choose either a ketogenic or low GI nutrigenomic diet similar to our California Coastal or Forager diets. As the name of the study suggests, results were divided into two phases: after 6 months and then again after 18 months.
After phase 1, participants in the ketogenic diet group saw greater weight loss than the DNA diet group. However, after the 18 month follow up, subjects in the DNA diet group lost on average 19 more pounds than their ketogenic diet counterparts, in large part due to the inability of the keto group to maintain such a restrictive diet.
Further, at the end of the 18 month follow up period, the DNA diet group had much better results for total cholesterol, HDL-C, and fasting glucose.
Keto vs. DNA Diets After 18 Months
Why did the DNA diet work?
There has been a lot of chatter over the last several years about the effectiveness of DNA diets.Those of us who work in the nutrigenomics field know without a doubt they do, and there is a growing body of evidence to back up our confidence, however, there is no one size fits all DNA diet.
A DNA diet is only as good as its design, and a big part of designing a nutrigenetic plan involves using multiple genetic markers in concert to arrive at a program that addresses many aspects of wellness.
In our view, the nutrigenomic diet in the BMC study was successful for three key reasons:
- The DNA diet utilized a number of different genetic markers, rather than just a 2 or 3 as some previous studies have done
- Exercise regimens were personalized based on genetics
- Adherence to the DNA diet was better
Polygenic risk scoring
Our lead geneticist and head of research, Dr. Aaron Gardner has done extensive work researching cystic fibrosis. Cystic fibrosis is a unique illness in that it is driven by one gene mutation. When the mutation is present so is cystic fibrosis. However, “one gene one illness” disorders are relatively rare. In many cases, as with heart disease, there are a number of factors that determine risk.
The trouble with many DNA diet studies is that they evaluated only a small number of genes (often 1-3). There are an estimated 30,000 genes in the human genome, so the idea that we can look at just one or two genes and construct a personalized diet isn’t realistic.
This is why the researchers in the BMC study included 28 SNPs for the patients placed on the nutrigenomic diet – they knew that utilizing several genes all linked to weight loss, digestion, food sensitivity, and exercise gave them a better shot at creating a truly personalized approach that would work. The use of many genes to create a risk score is known as polygenic risk scoring. Polygenic risk scoring uses multiple genetic factors to arrive at an algorithm that can help people find personalized solutions to diet and exercise, or in other contexts to chronic illness. This is what we do at Gene Food, we use a concert of genetic factors to categorize our customers into one of twenty diet types.
The end result in the BMC study wasn’t just much greater weight loss, it was also greater cardio metabolic health.
While the exercise duration was standardized between both groups, the nutrigenomic group received additional advice on how to tailor diet to genetics based on 6 genes:
To their credit, study authors helped the ketogenic diet group measure to confirm they were in a state of ketosis. The issue was maintaining that state.
Of the 13 members of the ketogenic diet group who had trouble maintaining ketosis, 8 had trouble with an excess of carbohydrates and 5 had issues with too much protein. Further, the ketogenic diet group lost a number of followers over time due to events on the social calendar and the restrictive nature of the diet. By contrast, the level of deviation from the nutrigenomic diet was much less. Although, like the ketogenic group, there were some slip ups for social events, overall the DNA diet group maintained the diet at a much greater rate over the 18 months than the ketogenic group.
Greater adherence for DNA diet interventions is nothing new, in fact it is an emerging trend in the scientific literature. For example, this study which appeared in the prestigious BMJ, found much greater adherence to a nutrigenomic diet compared with a population based diet intervention for weight loss. The BMJ authors concluded:
Weight management interventions guided by nutrigenomics can motivate long-term improvements in dietary fat intake above and beyond gold-standard population-based interventions.
As our research team reviewed these weight loss studies, some key takeaways emerged.
First, although there is a time and a place for ketogenic diets, especially in the context of epilepsy, high fat keto style diet won’t work for many people. The diets aren’t sustainable over a period of years, and for a segment of the population, will increase the risk for heart disease over time.
Next, personalized nutrition is here to stay. Unfortunately, consumers are inundated with a constant stream of weight loss commercials and fad diets. While interventions like Prolon and intermittent fasting have great promise, and are rooted in good science, simply suggesting that all overweight people follow a keto style diet is bad advice. In the BMC study, the DNA diet didn’t just slightly outperform keto, it blew it out of the water, and not only for weight loss, but for important biomarkers like cholesterol and fasting glucose.
Last, when designing nutrigenomic diet plans, it is important to utilize a polygenic risk scoring approach rather than looking at one or two genes.
Are you following a ketogenic diet for weight loss? We’d love to hear from you in the comments.