You've heard it before: oatmeal reduces cholesterol. Oatmeal producers have obtained permission from the FDA to use a cholesterol-reducing claim. The American Heart Association provides a (paid) endorsement of Quaker Oats.
I've lost count of the times I've asked someone whether they ate a healthy breakfast and the answer was "Sure. I had oatmeal."
Is this true? Is oatmeal heart healthy because it reduces LDL cholesterol?
I don't think so. Try this: Have a serving of slow-cooked (e.g., steel-cut, Irish, etc.) oatmeal. Most people will consume oatmeal with skim or 1% milk and some dried or fresh fruit. Wait an hour, then check your blood sugar.
If you are not diabetic and have a fasting blood sugar in the "normal" range (<100 mg/dl), you will typically have a 1-hour blood glucose of 150-180 mg/dl--very high. If you have mildly increased fasting blood sugars between 100 and 126 mg/dl, postprandial (after-eating) blood sugars will easily exceed 180 mg/dl. If you have diabetes, hold onto your hat because, even if you take medications, blood sugar one hour after oatmeal will usually be between 200 and 300 mg/dl.
This is because oatmeal is converted rapidly to sugar, and a lot of it. Even if you were to repeat the experiment with no dried or fresh fruit, you will still witness high blood sugars in these ranges. Do like some people and pile on the raisins, dried cranberries, or brown sugar, and you will see blood sugars go even higher.
Blood sugars this high, experienced repetitively, will damage the delicate insulin-producing beta cells of your pancreas (glucose toxicity). It also glycates proteins of the eyes and vascular walls. The blood glucose effects of oatmeal really don't differ much from a large Snickers bar or bowl of jelly beans.
If you are like most people, you too will show high blood sugars after oatmeal. It's easy to find out . . . check your postprandial blood sugar.
In past, I recommended oat products, specifically oat bran, to reduce LDL, especially small LDL. I've changed my mind: I now no longer recommend any oat product due to its blood sugar-increasing effects.
Better choices: eggs, ground flaxseed as a hot cereal, cheese (the one dairy product that does not excessively trigger insulin), raw nuts, salads, leftovers from last evening's dinner.
Could mustard--yes, the yellow condiment you smear on hot dogs--be a super heart healthy food in disguise?
Consider that mustard contains:
Vinegar
Turmeric
No appreciable sugar
The vinegar slows gastric emptying, resulting in slower absorption of any carbohydrates and a reduced glucose area-under-the-curve. Of the little fats contained (about 3 grams per 1/4 cup), most are desirable monounsaturates. Mustards are relatively rich in selenium, with 20 mcg per 1/4 cup, helpful for protection against cancer and thyroid disease, and magnesium, 31 mg per 1/4 cup.
Turmeric is added to most mustards. One of the constituents of turmeric, curcumin, the substance that confers the bright yellow color, has been a focus of interest for its anti-inflammatory effects. Curcumin has been documented to reduce activity of the inflammatory enzymes cyclooxygenase-2 (COX-2), lipoxygenase, and reduce activity of inflammatory signal molecules, tumor necrosis factor-alpha (TNF-a), interleukin (IL)-1,2,6,8, and 12, and monocyte chemoattractant protein (MCP). Curcumin also has been shown to reduce LDL oxidation, a potentially important step in atherosclerotic plaque formation. Turmeric is used as a tea by Okinawans. (Hmmmm . . . )
Turmeric content of mustard can vary, of course. Likewise, sugar content. Look for mustards that are not sweetened, so avoid honey mustard in particular. Look for hot, brown, horseradish, Dijon, etc. If there is a downside to mustard, it's sodium content, though the 709 mg per 1/4 cup should only be a problem for those who are sodium-sensitive (African Americans, in particular).
So perhaps mustard isn't exactly a super health food. But it may have some bona fide health effects and should be used generously especially if you are concerned about blood sugar and inflammatory phenomena.
There is no doubt that exercise yields benefits across a spectrum of health: reduced blood pressure, reduced inflammation, reduced blood coagulation, better weight control, stronger bones, less depression, reduced risk for heart attack.
Exercise also influences blood sugar. Diabetics understand this best: Exercise reduces blood sugar 20, 30, 50 or more milligrams. A starting blood sugar, for instance, of 160 mg/dl can be reduced to 80 mg/dl by jogging or riding a bicycle. (I recently had brunch at an Indian restaurant with my family. Blood sugar one-hour postprandial: 134 mg/dl. I was sleepy and foggy. I got on my stationary bike and pedalled at a moderate clip for 60 minutes. Blood sugar: 90 mg/dl.)
Could the reduction of blood sugar with exercise be THE reason that exercise and physical activity provide such substantial benefits?
Think about it. Reduced blood sugar:
1) Reduces risk for future cardiovascular events. 2) Reduces glycation of proteins, i.e., reduced glucose binding to proteins like the ones in artery walls and the lenses of your eyes. 3) Reduces blood coagulation 4) Reduces endothelial dysfunction (abnormal artery constriction that leads to atherosclerosis)
This might explain why it doesn't require high levels of aerobic activity to derive benefit from exercise, since even modest efforts (e.g., a 15-minute walk after eating) reduce blood sugar substantially.
The incredible 33-year, 18,000-participant Whitehall study tells us that a postprandial (after-eating) blood sugar of an impossibly-difficult 83 mg/dl is required to erase the excess cardiovascular risk of blood sugar. Could this simply be telling us that physical activity or exercise is required to suppress blood sugars to these low levels?
It makes me wonder if an index of the adequacy of exercise is your post-exercise blood glucose.