Low cholesterol and diabetes and obesity

Because of heightened interest in people with very low cholesterol levels, scientists at the University of California, at San Diego, compared men and women across a range of cholesterol levels in a large population study for multiple sociologic, biologic, and medical attributes.[1]

Two sex-specific age groups were studied, 30–54 years and 55–79 years.

The researchers say "In general, comparisons between deciles for each of these four age-sex groups revealed only minor differences for demographic variables; systolic or diastolic blood pressure; fasting plasma glucose; weight; height; obesity; cigarette smoking; dietary eggs or milk; medications for hypertension, hyperglycemia, hyperuricemia, or hyperlipidemia; family history of myocardial infarction, diabetes, or stroke; and personal history of myocardial infarction, congestive heart failure, hypertension, or stroke. Thus, the lowest and the middle deciles of plasma cholesterol in this population shared similar sociologic, biologic, and medical profiles."

What they did find — unexpectedly — was that there were "somewhat more diabetics in the lowest decile[10%], and greater obesity and triglyceride levels in the lowest decile diabetics compared to either lowest decile non-diabetics or middle decile diabetics, perhaps suggesting a metabolically distinct subset.

The question then was: Did the lowest levels of cholesterol increase the risk of diabetes and obesity? or did having diabetes and obesity tend to lower cholesterol? or were the two purely coincidental?

Reference
1. Franzblau A, Criqui MH. Characteristics of persons with marked hypocholesterolemia. A population-based study. J Chronic Dis 1984; 37: 387-95.