by Craig Weatherby
With diabetes threatening to cripple millions while it swamps America's finances and health care system, the need for lifestyle-based prevention has long past the point of urgency.
A diagnosis of metabolic syndrome (MetS) raises your risk of developing type II diabetes and heart disease.
You are considered to have MetS if you show any three of these six signs:
abdominal obesity, hypertension, sticky blood, a poor blood fat/cholesterol profile, inflammation in the blood, or high blood sugar levels (AHA 2010).
University studies provide ample evidence that exercise, balanced whole-food diets, and omega-3 fats from fish tend to deter the risk factors for diabetes, including key components of MetS.
While omega-3s are not clinically proven to lower blood sugar levels—though they have that effect in some animal studies—omega-3 fish oil supplements are clinically proven to lower blood triglyceride (fat) levels and improve people's blood cholesterol profiles.
And although omega-3s do not lower LDL (“bad”) cholesterol levels, they do something with more proven impact on the risk of heart disease… they raise the HDL/LDL ratio and lower levels of dangerous VLDL cholesterol (Harris WS et al. 1988; Roche HM et al. 1996; Hartwich J et al. 2010; Perez-Martinez P et al. 2010).
Every meal we eat impacts our blood cholesterol and fat (lipid) profile, and your preference for various dietary patterns—and your body's reactions to them—will affect your risk of cardiovascular disease and diabetes.
Sharp increases in blood triglyceride (fat) levels following a meal are one of the major abnormalities found in people with MetS.
People with MetS also tend to suffer spikes in blood levels of an undesirable, cholesterol-packed fatty compound called triglyceride-rich lipoprotein.
Spanish researchers decided to measure the immediate impact of diets featuring different amounts and kinds of dietary fat, by testing the blood of MetS patients after eating each kind of meal.
And this intriguing clinical research suggests that supplemental omega-3s can blunt the ill effects that a suboptimal diet exerts in MetS patients.
Omega-3s deter diet-driven rises in blood fat levels
People with or at risk of MetS are sometimes advised to eat a diet low in fat and high in complex carbohydrates (e.g., colorful vegetables and whole grains).
However, prior research has called the wisdom of that approach into question (Garg A et al. 1988; Volek JS et al. 2009).
Sure enough, Spanish researchers report that a low-fat, high-complex carbohydrate diet had “several detrimental effects” in MetS patients, including higher levels of total triglycerides and undesirable triglyceride-rich-lipoproteins.
The new Spanish trial tested the effects of four different diets, all providing about the same number of calories, on blood fat profiles in 164 people with metabolic syndrome:
High in fat, mostly saturated;
High in fat, mostly monounsaturated (e.g., olive oil)
Low in fat, high in complex carbohydrates (whole grains and vegetables)
Low in fat, high in complex carbs plus a daily omega-3 fish oil supplement (1.24 grams a day, or just a bit more than in a standard 1,000mg capsule)
At the outset, all the participants had similar blood fat responses after eating a meal.
But by the end of the three-month trial, those on Diet #4 (low-fat/high-carb plus omega-3s) and Diet #2 (high-fat/monounsaturate-rich) showed healthier blood fat effects.
In fact, participants in the omega-3 fish oil group suffered no ill effects and had lower levels of triglycerides, compared to people eating a high-fat diet rich in saturated fats (Diet #1) or the low-fat/high-carb diet without fish oil (Diet #3).
And we said, there's good evidence that omega-3s exert these beneficial blood fat effects in most dietary contexts.
Interestingly, a diet rich in monounsaturated fats yielded lower blood fat levels than either the test diet or a diet high saturated fats (Monounsaturated fats are most abundant in avocadoes, olives, olive oil, macadamia nut oil, and hi-oleic sunflower oils).
The Spanish team's findings affirm the idea people with metabolic syndrome could benefit from higher omega-3 intake … and support prior research suggesting that olive oil and other foods rich in monounsaturated fats can exert a positive effect on blood lipid profiles.
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