ho hum

Ethnic differences in levels of HDL, the "good" cholesterol, may be due, at least in part, to diet, a new study from Canada suggests.

South Asians ate the most carbohydrate and had the lowest HDL cholesterol levels, while Chinese individuals ate the least carbohydrate and had the highest levels of the beneficial blood fat, Dr. Anwar T. Merchant of the Population Health Research Institute in Hamilton, Ontario and colleagues found.

Previous research has identified ethnic differences in cholesterol and other blood fat levels that couldn't be explained by genes, obesity, lifestyle factors or diet, Merchant and his team note, but these analyses usually looked at dietary fat, not carbohydrate consumption. When calories from carbohydrates replace energy from fat in a person's diet, both LDL and HDL cholesterol levels fall while triacylglycerol levels rise, the researchers explain.

To investigate the role of carbohydrate and HDL levels in a population containing a variety of ethnic groups, Merchant and his colleagues analyzed the diet and blood fats of 619 Canadians of Native American, South Asian, Chinese and European descent. The researchers report their findings in the American Journal of Clinical Nutrition.

As mentioned, South Asians ate the most carbohydrates, followed by Europeans, Native Americans, and Chinese. After adjustment for several factors including age, ethnicity, body mass index and alcohol intake, the association between carbohydrates and lower HDL cholesterol remained, with people consuming the most carbs having an average level of 1.08 mmol/L, compared to 1.21 mmol/L for those who ate the fewest carbohydrates.

Each additional 100 gram per day of carbohydrates was tied to a 0.15 mmol/L drop in HDL cholesterol. Triacylglycerol levels also rose in tandem with carbohydrate intake.

The researchers also found that consuming more sugar-sweetened soft drinks, juices and snacks was tied to a lower HDL level.

"Differences in HDL and triacylglycerols observed in different ethnic groups may be due in part to carbohydrate intake," the researchers write. "Reducing the frequency of intake of sugar-containing soft drinks, juices and snacks may be beneficial."

terrymorse 

So is that a good thing, or a bad thing? HDL drops, but so does LDL (the bad one).

!!Comatoa$ted

It would be nice to know what sort of carbs that they are talking about, if it is junk food like they say, or is it just carbs in general? Is it that the extra carbs provided in the diet by sweet drinks cause an excess of CHO's that are causing the problem and not the CHO's themselves, in essence the extra calories are the cause of the problem?

slim_77

In addition to what !!comatoa$sed said, the replacement of carbs with some other sustenance must occur with the other groups and therefore the kind and quality of those other calories must be taken in to account. In addition, carbs are cheap...cheap carbs are the easiest and most common source of food for many Americans but, in particular, low income Americans (thus >obesity); whereas high protein diets are more common among the affluent. Even in this case the quality of the protein is very important. Their *complete* diet must be accounted for. I can't imagine that the "previous studies" failed to account for these factors...

"carbs" alone? No way. The reporter must have edited too much out.

!!Comatoa$ted

I don’t think that is a media report, I read the abstract and it says the same thing, only some numbers and statistics are not shown in the OP. It is a 2007 article, and AJN's embargo is 1 year, so all that is available for viewing is the abstract, unless one wants to pay to see it.

They do mention sweetened drinks though, this infers that the proportion of the extra CHO's are from refined sources. It may not be easy to elevate CHO's to a detrimental level if one were to eat only unrefined CHO's. And as benefit from unrefined CHO’s you would be getting fibre and many other nutrients, not available in many sweetened drinks.

ho hum

Aren't there two types of LDL? Triglycerides climb on a high carbohydrate diet and I think this also constitutes an increased health risk. All I can say antecdotally, is that my HDL and LDL are better and my triglycerides are lower on a restricted carbohydrate intake. HgA1C is also better. Low carbohydrates have not been without their drawbacks though. I am not able to perform as well on my bike and I occasionally get muscle cramps if I am not careful with taking magnesium, calcium and potassium. I could probablly eat more carbohydrates if I could find more time to ride.

!!Comatoa$ted

Are you a diabetic?

slim_77

Ah, the abstract is tantalizingly incomplete...dang (blessed) IP protections. I caught where I read too quickly the first time.

I have a low HDL level and I consume lots of carbs (cycling...duh!), but a great proportion are unrefined. In addition, I am a diabetic (Type 2) and avoid refined carbs (soda, candy, junk, etc.) yet my HDL is still slightly lower than it should be according to my last lab results (not sure of the triacylglycero level). I wonder what their conclusions are...and to echo Terry...is it good or bad???

And still, there must be multiple elements of diffusion in their diets that ethnicity alone does not answer, ones that are substantial enough and complex enough to go beyond just the quantites of refined carbs ("the each additional 100g/day"). Perhaps the complete study accounts for the "whole diet" factor...

anyway, just my social sciences pound of .02

slim_77

I just misdiagnosed myself!

I'm Type 1!