Many people say that keto diets are easiest to adhere to and have the fewest drop outs.
Today we look into this matter and see, is this really true?
An objective way to measure ketogenic adherence is via ketone levels (Nymo et al., 2017; Cipryan et al., 2018). If ketones increase, we know that the person is restricting carbohydrates.
If ketone levels fall, then participants are probably not adhering to the diet.
After doing a systematic search of the ketogenic literature, we gathered together ten suitable studies. You can see data from these ten studies in the line chart below.
Eight groups never reached ketosis above 0.5 mmol/l. Four were in borderline ketosis (0.3–0.49 mmol/L BHB) by the end of the study.
Only two groups were clearly in ketosis at one point during the study.
The info we gathered showed primarily diabetics and the obese, struggle to adhere to the ketogenic diet.
Athletes and similar + those on metabolic wards (people specifically fed a set diet) find it easier to adhere.
This means the obese and the diabetics were struggling with lower carbs and eating them in their diets, meaning they were not adhering to their diet.
One may say that one becomes adjusted to ketones and that the levels will naturally decrease.
However work with athletes and metabolic wards show this not to be the case, which would be if the body adjusted itself.
In these types of studies, people have much higher BHB levels (Beta-hydroxybutyrate):
Hall et al., 2016 (metabolic ward): 0.76 mmol/L BHB over 4 weeks
Goday et al., 2016 (feeding study): 1 mmol/L BHB at week 4 Johnston et al., 2006 (feeding study): 0.72 mmol/L BHB at week 2
Gomez-Arbelaez et al., 2018 (feeding study): 1 mmol/L BHB at C-2 (week 5.6)
Burke et al., 2017 (elite athletes): 1.8 mmol/L BHB at week 3 Wilson et al., 2017 (close follow-up): 0.85–1.4 mmol/L BHB at weeks 4–10
These 2 graphs taken from 2 of the studies equally show BHB increases so does not support the theory of the body adjusting.
If there was going to be adaption it would have shown in elite athletes and in strictly fed metabolic wards.
The reality is that under reporting when eating away from control is common. These following studies all show under reporting. It is common!
Baranowsky et al., 1986; Schoeller, 1990; Drougas et al., 1992; Lichtman et al., 1992; Fries et al., 1995; Buhl et al., 1995; Schoeller, 1995; Heitmann and Lissner, 1996; Scagliusi et al., 2003; Okubo et al., 2008; Scagliusi et al., 2008; Bartholome et al., 2013; Capling et al., 2017.
Our view is most likely ate more carbs than what they reported and show that keto diet is not as easy to adhere as some people would make you believe.
In terms of drop outs between high fat/low carb and low fat/high carb diets, the numbers were almost identical. The ketogenic diet studies had a total of 1307 participants, of which 319 (24.4%) dropped out from the studies.
The control diets had a total of 1294 participants, of which 311 (24%) dropped out. Almost exactly the same, slightly in favour of higher carb group.
Take home view? Follow the diet YOU can follow – not what people tell you is the easiest. At the end of the day, it is a personal matter of what you find most satisfying and easy to follow.
At this point, the process becomes easier and more of a life style and less of a chore.
We hope this helped you!
