Monday, January 30, 2012

The Doctor Strikes Again

I had the great opportunity to visit my newest doctor today. Not a routine visit but a pre-op appointment. Nothing serious - an endoscopic sinus surgery to alleviate years of sinus issues. I had to get a full exam done, and in the process learned they were going to take blood again. Excitedly, I asked if they were doing another lipid profile at which point they stated yes - and much more!

The results should be interesting as this time around I did not fast, and actually had an apple earlier in the day. It is like Christmas all over again! One interesting conversation did come up with the doctor. I normally tend to just use him as a means to an end, however I wanted to ensure I knew what his feelings were about cholesterol.

I inquired whether my HDL components would be broken down for this panel as it was not previously. This sparked some interested in him reviewing my last LDL reading...which was 117. Keep in mind my lipid profile stated my LDL was "abnormal". He explained:

Your LDL reading was a bit on the high side last time. If it gets any higher, say 130 treatment may be necessary to get it down.

Rather than floor him with clinical trials and research, I wanted to see what he knew about low-carbohydrate affects on LDL particle size. I asked "Don't you think my LDL increase may be of little worry due to the fact I am eating low-carb and my LDL particle type is mostly type A?"

"No, no!" he waved me off. "You need to start decreasing some of the fatty foods you eat, such as red meat, fatty milk, cheese, cream..."

Honestly, I was floored and almost speechless. This is the first doctor I've ever actually give this advice. But after reading all this literature, studying nutrition and more, I was still not prepared to hear it from someone I'm supposed to trust. Before leaving the doctor's office, I decided to reverse my decision and opt-in to the doctor's newsletter as I cannot find his e-mail address anywhere. I really want to e-mail him the JAMA article from 2007 covering the A-Z Study.

The Journal of the American Medical Association
Comparison of the Atkins, Zone, Ornish, and LEARN Diets for Change in Weight and Related Risk Factors Among Overweight Premenopausal Women
The A TO Z Weight Loss Study: A Randomized Trial

Christopher D. Gardner, PhD;
Alexandre Kiazand, MD;
Sofiya Alhassan, PhD;
Soowon Kim, PhD;
Randall S. Stafford, MD, PhD;
Raymond R. Balise, PhD;
Helena C. Kraemer, PhD;
Abby C. King, PhD

http://jama.ama-assn.org/content/297/9/969.full

This study set to discover the benefits that low-carbohydrate diet may bring when compared with other standard low-fat diets. The one interesting part about LDL comes here:

Many concerns have been expressed that low-carbohydrate weight-loss diets, high in total and saturated fat, will adversely affect blood lipid levels and cardiovascular risk.34-36​ These concerns have not been substantiated in recent weight-loss diet trials. The recent trials, like the current study, have consistently reported that triglycerides, HDL-C, blood pressure, and measures of insulin resistance either were not significantly different or were more favorable for the very-low-carbohydrate groups.12-16​

The exception to this pattern has been LDL-C concentrations. Two of the most consistent findings in recent trials of low-carbohydrate vs low-fat diets have been higher LDL-C concentrations and lower triglyceride concentrations in the low-carbohydrate diets.17 Although a higher LDL-C concentration would appear to be an adverse effect, this may not be the case under these study conditions. The triglyceride-lowering effect of a low-carbohydrate diet leads to an increase in LDL particle size,
which is known to decrease LDL atherogenicity.37​-39 In the current study, at 2 months, mean LDL-C concentrations increased by 2% and mean triglyceride concentrations decreased by 30% in the Atkins group. These findings are consistent with a beneficial increase in LDL particle size, although LDL particle size was not assessed in our study. In addition, we examined non–HDL-C concentrations as an alternate indicator of atherogenic lipoproteins—a variable not substantially influenced by changes in triglyceride concentrations26​—and observed no significant differences among groups at any time point.

Therefore, we interpret these findings to suggest that
there were no adverse effects on the lipid variables for women following the Atkins diet compared with the other diets and, furthermore, no adverse effects were observed on any weight-related variable measured in this study at any time point for the Atkins group. Further examination of the dietary effects on lipid variables would benefit from analyses of lipoprotein particle subfractions and follow-up of longer than 12 months.

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