Lipids on a Ketogenic diet
Q. I am an Emergency Physician living in Denver and have long been interested in nutrition and wellness. I have been a fan of yours for years. My journey has led me through the works of Gary Taubes to Phinney and Volek's excellent books on nutritional ketosis. My dietary recommendations to patients (yes, I speak to some of my Emergency Department patients about their diet) have taken a radical turn with the reframing of the information that these and other authors have provided in the last few years.
I personally have long been an endurance athlete, and decided to
try the HFLC diet to personally assess it's effects on my
endurance, wellness and more traditional measures of cardiovascular
risk. 10 weeks into the experiment I was down to my high school
weight (though I started at a relatively lean weight). My ability
to complete long bike and run workouts was undiminished, even with
minimal to no caloric intake during exercise. My energy level
seemed steady and hunger during the day was somewhat diminished.
However, I monitored my serum ketones and found that it was very
difficult for me to stay in the 0.5-1.5 range considered to be
optinal NK. I would routinely measure ketone levels of 0.1-0.4.
Fearing that I was in some sort of dangerous middle ground, between
NK and the standard American diet, I decided to check my lipid
panel. I was surprised to see a marked rise across the board in my
numbers from last year:
Total cholesterol went from 173 to 270. LDL from 96 to 158. Triglycerides from 63 to 112 and HDL from 64 to 90. Trig/HDL from 0.98 to 1.24.
Now I realize that there is controversy around the significance of lipids and their role in atherogenesis, but can a 65% jump in LDL really be dismissed as totally harmless?
I've read the studies on saturated fat intake and lipids as well as CV risk, and I consider myself a variant from expected outcome. Is it possible that some people respond badly to this diet?
I find myself somewhat stunned and unsure of how to proceed
personally and in terms of what I recommend to patients. I am torn.
Do I: Adjust the types of fat I consume? (Sat>MUSF>PUSF)
Change the macronutrient balance from my current 65%Fat 10% Carb 25% protein?
Lower total calories?
Double down and see if the numbers normalize with more time in (near) NK?
I'd really value your input.
The weight of LDL is greater because very likely LDL particle size increased. That's a good thing.
I would just get a VAP cholesterol test done to verify.
As far as nutritional ketosis; I don't quite agree necessarily with the numbers. The ideal situation would be that you would burn the ketones as they are formed. In this case your serum ketones would be close to zero. It must be realized that serum ketones reflect the ketones not being burned.
As far as your macronutrient ratio; also not particularly important. You will never really know what you are eating. You are your cells. It is your cells that eat. You merely process the food for them. What you want to do is eat to regulate the hormones (particularly leptin) that will dictate what your cells eat today and what they will want to eat tomorrow.
The only macronutrient that I would be sure to keep track of is the protein intake. It is not the macronutrient ratio here that would be important; it would be the total grams of protein that would be determined by your activity level and lean mass. Then eat as few non-fiber carbohydrates as is feasible. The majority of your diet would be fat to appease hunger and supply fuel. I would try not to eat excessive omega 6 fatty acids. However, the ratio of types of fatty acids, once you are adept at burning fat and ketones, is also less important, as you will tend to burn what you eat before much of their other physiological effects manifest themselves. The vast majority of studies on types of fatty acids were done in carbohydrate adapted, and therefore fat challenged, animals and people.
The only number that is a little bit puzzling is the triglycerides that have gone up a little. I'm not sure why that is without perhaps knowing more information. Are you perhaps eating too much protein? Have you measured your glucose and insulin levels? Do you know if they went up? Are you perhaps over exercising and therefore increasing gluconeogenesis?
Thanks for the questions and the fine work that you are doing "in the trenches". Let's keep in contact.