I love good research about diet and on the surface I was excited about this one, until I read more.
The NIH sponsored and designed this research without an axe to grind, so it is objective – Good. It measured a ton of interesting parameters, like DXA for abdominal fat loss to differentiate from plain old weight loss – Good. The study randomly placed people into the low carb high fat (LCHF) with a whopping 75% of calories coming from fats and low fat high carb (LFHC) which had only 10% of calories coming from fats. Halfway through the study participants switched to the other group – Good. Furthermore, it was in a confined space where everyone ate and where the food was monitored to a “T”, no more of this questionnaire about what you ate last year – Good.
But then it starts to go awry, participants were under 30 years old and each diet was only completed for 2 weeks. Dieta in it’s Greek root means way of life. A 2-week intervention is far from my clinical goal for someone. And the randomness of the diet application rubs me wrong, which I’ll explain in a second.
How did they do you ask? Each diet displayed measurable weight loss even though participants of both groups were told to eat “as much as they felt necessary”. Remember both groups were taken out of their routines, knew they were in a diet study and were not allowed processed food or sugary drinks. It was interesting that people ate >20% more calories while in the high fat low carb grouping. I see this regularly when people start low carb high fat, since it takes a little while, more than 2 weeks, to appreciate that high fat foods are really high in calories. Strike one for LCHF, right? But when participants were on the LFHC diet their blood sugars were erratic and higher. Given the profound health complications of prediabetes and diabetes, strike one for low-fat, right?
The biggest issue I have here is the lack of individualization. This is the demise of medical research and medical practice overall though. One-size-fits-all is how we are able to steer healthcare providers to provide one set of dietary advice for “all people wishing to lose weight” or for “all people at high risk of a heart attack.” If I were stuck in the land of universal standards-of-practice with dietary advice, I would fail half the time. For baseball .500 is still a good batting average, but in medicine, this sucks.
If you have blood sugar irregularities like I tend to, clearly the low-fat diet is wrong for you. If you have no issue with blood sugars and tend toward very high triglycerides and cholesterols (like a total over 280 mg/dL) you may be better with a lower fat and more pronounced fibrous vegetable intake.
Find out where your vulnerabilities lie. Here are three simple lab results that I think everyone should know. Getting a lab panel directly could help – see Discovery Panel #1 here:
1 – Erratic or questionable blood sugar is anyone with a HgbA1c of <5% or >5.6%. If you are above or below this range, the LCHF-type diet can work better for you.
2 – If your adult fasting insulin is >8 uIU/mL, you will not do as well with the high carb intake – so lean toward the high fat low carb. If weight gain is an issue, reducing elevated insulin is usually the best correction to start with.
3 – Triglycerides (TG) of >100 indicate too much fat storage, whatever strategy you employ, this # should improve. For this and the other measures above…test and retest in 3 months.
Self-metrics liberate us from the one-size-fits-all diet and fitness advice. I will still read multiple studies weekly for you. But as of now, I remain proud of what I wrote in The Blood Code book so many years ago. I ran my labs a couple months ago, and I continue to stick with my higher fat and lower carb diet. What works for you?