At the Kahn Center, we teach the science of whole food, plant diets, generally lower in fats, for heart disease prevention and reversal. This is based on studies by legends like Lester Morrison, MD, Nathan Pritikin, Dean Ornish, MD, Caldwell Esselstyn, MD, Joel Fuhrman, MD and others.
A variation on this approach has been called a "vegan keto" diet that is low in carbohydrates and higher in fats like tofu, avocado, olive oil, nuts, and seeds. There are online guides describing vegan keto diets. There is no data that vegan keto diets and prevent or reverse heart disease.
A new study reports that even one day of a low-carb diet, even if total calories are not reduced, may have favorable metabolic impacts raising the question if even one day a week of a low-carb diet can be a consideration.
STUDY
The authors aimed to investigate the independent acute metabolic effect of carbohydrate restriction at varying energy levels. Twelve, (six female) healthy overweight/obese participants (27 years on average) completed this three-way study.
Volunteers followed three diets for one day (36 h, covering the intervention day and overnight fasting): a normal carbohydrate, energy-balanced diet (nEB, 55% CHO), a low-carbohydrate, energy-balanced diet (LCEB, 50 g/day CHO), and a low-carbohydrate, energy-restricted diet (LC25, 50 g/day CHO with 75% energy restriction).
Both low-carbohydrate with and without energy restriction diets induced comparable decrease in triacylglycerol and respiratory quotient.
Compared to a non-restricted carbohydrate, energy-balanced diet, postprandial glucose levels significantly increased in the LCEB arm and showed a rising trend in the LC25 arm.
CONCLUSIONS
These findings demonstrate that carbohydrate restriction, without altering calorie intake, can elicit effects similar to those observed in short-term fasting. The authors found that, regardless of how many calories the participants consumed, eating a low-carb diet encouraged their bodies to burn fat for energy – just like on a fasting diet.
This is good news as you may not have to slash your calories so drastically on fasting days – simply cutting out carbs might offer similar fat-burning benefits.
Alternating between low-carb days and regular eating days seems to improve metabolic health – while also being a more manageable dietary pattern for carb-lovers.
I have experimented with "vegan keto" diets in the past but it has been a while, for periods for up to 2 weeks. I may experiment now with a single day of a low carb version of a whole food, plant diet, keeping protein low but healthy plant fats high. Discuss any changes in your diet with your healthcare team.
