Dr. Tim Says...

Chicken skin: to eat, or not to eat 06/19/17
Change is here 06/12/17
Medical technology 03/27/17
The science behind the DASH diet, an overview: Part Two 08/01/16
The science behind the DASH diet, an overview: Part One 07/25/16
How the Standard American Diet (SAD) affects the brain (Part Two) 05/26/16
How the Standard American Diet (SAD) affects the brain 05/23/16
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Chef Tim Says...

Deviled Eggs 04/24/17
Roasting Fruit 04/03/17
Papadum 03/20/17
Capers make it better 02/06/17
Mustards: The Christmas Basket Challenge, Part 5 01/26/17
Canned Tuna from Spain: The Christmas Basket Challenge, Part 4 01/16/17
Ginger and Rice Noodles: The Christmas Basket Challenge, Part 3 01/12/17
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Dr. Tim Says....



Lowering Cholesterol

There is a pretty clear link between high serum cholesterol and heart disease. When I say "serum" cholesterol I mean the blood test that your doctor performs. It's not just the total cholesterol that we care about but the lipid panel. Lipids are fats and the various types of fats that we measure are the High Density Lipoprotein (HDL), Low Density Lipoprotein (LDL) and triglycerides. The key is there is a difference between these lipids and the cholesterol we consume.

For most of us dietary cholesterol, the cholesterol we eat, has not been clearly linked with any effect on our serum cholesterol. Quite simply, it appears that consuming cholesterol is not really something that we need to focus on. For instance, one food that has never been shown to have an effect on cholesterol is eggs. That's right, eggs. In a recent article in Circulation (2008;117: 512-516) researchers found no association between the amount of eggs the subjects ate and any change in their total cholesterol, HDL cholesterol, or ratio of total cholesterol to HDL cholesterol.

OatmealHow can you lower your cholesterol? For the most part we don't know the exact mechanisms for lowering cholesterol. Fiber is one nutrient that does help lower cholesterol, and it appears that the mechanism has to do with fiber's effect on the absorption of dietary cholesterol and other fats. You likely already know that foods that are high in fiber, especially those with soluble fiber such as beans, oat bran, oatmeal and rye, are clearly shown to improve cholesterol profiles. That's not to say that insoluble fiber, such as that found in fruits, whole grain products like whole wheat flour, whole grain breads and pastas, as well as cereal grains like rice, wild rice and seeds, should be ignored. These guys are great too!

We know that good quality oils and fats that are high in monounsaturated fats change cholesterol profiles for the better, but there's more to it than the fat itself. In the case of olive oil many of the flavonoids, polyphenols and other antioxidants are what appear to affect cholesterol. These are similar to compounds in such things as chocolate, red wine and fruits that help change the composition of the lipids in the body.

There are, however, a few foods that have an effect on cholesterol that may surprise you:

1. Chocolate

Chocolate BarYep, you read that correctly, chocolate. In one study 28 healthy males between 18 and 20 years old were given 105 grams of milk chocolate per day for 14 days. They showed a decrease in total cholesterol and LDL cholesterol.  (Clin Dev Immunol 12, 11 – 17) Interestingly, the researchers also showed a mild drop in blood pressure. There have been numerous other studies showing that chocolate increases the good (HDL) cholesterol. (Am J Clin Nutr 74, 596 – 602) (J Am Coll Nutr 23, 197 – 204)

2. Cocoa

Hot CocoaYum. A cup of hot cocoa! In one study 160 adults were given varying "doses" of cocoa over a 4 week period. Blood samples were collected at baseline and four weeks. They found that oxidized LDL concentrations decreased in the low-, middle-, and high-cocoa groups compared with baseline. (This is not LDL cholesterol but the oxidation process of the LDL "packet" is now associated with artherosclerosis.)

When they looked at those participants who had higher cholesterol levels at baseline they found that their LDL cholesterol decreased and the plasma HDL cholesterol concentration increased, relative to baseline in the low-, middle-, and high-cocoa groups. The results suggest that antioxidant substance such as polyphenols derived from cocoa powder may contribute to a reduction in LDL cholesterol, an elevation in HDL cholesterol, and the suppression of oxidized LDL. (J Nutr 137, pg 1436-1441)

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