![]() Here we go again. A new study appears to link high fat intake to insulin resistance and postmeal blood sugar spikes. All study participants had Type 1 diabetes and were assigned to consume either two low-fat meals and one high-fat dinner or three low-fat meals. Researchers reported that those receiving the high-fat dinner required more insulin (12.6 units vs. 9 units for the low-fat dinner) and that their postprandial blood sugar and insulin levels were higher and stayed high for several hours after eating. There are a few red flags regarding this study. First of all, the sample size was extremely small (seven people). And this line is revealing: "The two dinners received by each subject had identical carbohydrate and protein content but they differed in fat content (10 grams vs. 60 grams)." Now, the amount of carbs each meal contained wasn't reported (or at least I couldn't find it), but the amount of calories was. So by doing some math, we can get a ballpark estimate: The low-fat dinner contained on average about 600 calories, 10 grams of fat (90 calories), and let's say 25% protein (38 grams, 150 calories), which is probably being generous. That would leave approximately 90 grams (360 calories) of carbohydrate to make the 600 calorie total. So given the high carbohydrate content of the meal, these results aren't surprising. Fat delays the absorption of carbohydrate and makes accurate dosing of insulin extremely challenging (as CDE Gary Scheiner explains in discussing how to bolus for pizza). Previous studies have demonstrated the deleterious metabolic effects of consuming a high-fat, high-carbohydrate meal, which include insulin resistance, delayed postprandial hyperglycemia, and elevated triglycerides. However, there is research indicating that a high-fat, low-carbohydrate diet does not produce the same response; in fact, it results in lower insulin needs, less insulin resistance, and better postmeal blood sugar and lipid response in both Type 1 and Type 2 diabetes. And there's enough anecdotal evidence to support these findings many times over. So this study simply confirms what we already know: The combination of high fat and high carbohydrate is unhealthy. The best chance people with diabetes have of achieving better blood sugar control and decreasing insulin needs is to adopt whatever form of carbohydrate restriction works best for them. 1. Volek JS, et al. Carbohydrate restriction has a more favorable impact on the metabolic syndrome than a low-fat diet. Lipids 2009 Apr;44(4):297-309. 2.Volek JS, et al. Effects of dietary carbohydrate restriction vs. low-fat diet on flow-mediated dilation. Metabolism 2009 Dec;58(12):1769-77 3. Nielson JV, et al. Low carbohydrate diet int type 1 diabetes, long-term improvement and adherence: a clinical audit. Diabetol Metab Syndr 4: 23, 2012
4 Comments
3/30/2013 01:11:06 am
Until you see the individual data, you don't know anything. There is clear overlap of much of the data (especially since SEM is reported meaning that the errors are bigger than they look). Also, the study conforms to the double standard. If low-carb does well at 1 year, we have "concerns" about long-term effect. If low-fat shows something, it is "even a single meal can...." Poor science in basic chemistry justs wastes paper (or electrons). This kind of stuff actually hurts PWD.
Reply
3/30/2013 02:56:18 am
Thanks for pointing out the additional problems with this study, Dr. Feinman. I appreciate your expert opinion, as well as the work you did on the second study cited above.
Reply
Gerri
3/31/2013 03:11:29 pm
Conclusions from a seven person study? I'm not researcher or healthcare professional, but am another positive ancedote for low carb/high fat. Do a certain number of PWD ancedotes add up to a study:)
Reply
4/1/2013 12:12:00 am
Thanks, Gerri! Always great to hear about your continued success for low carb. I'm all for recruiting people who've done well with LC for such a study, but of course many organizations would discount it for not adhering to research protocols.
Reply
Your comment will be posted after it is approved.
Leave a Reply. |
Author
Franziska Spritzler, RD, CDE Categories
All
Archives
July 2019
|