Low-density cholesterol (LDL or “bad cholesterol”) and high-density cholesterol (HDL or “good cholesterol”) seem to get most of the coverage in popular level medical news reporting, but a third factor in most blood tests of lipids involves triglyceride levels, and they deserve more attention.
There Aren’t Good vs. Bad Types Of Triglycerides. Just Good vs. Bad Levels
A healthy level of triglycerides is actually very necessary for the energy cycle to continue in the body. Triglycerides are a highly energy efficient form of circulating fuel, and yet are also their own kind of gas can, in that they can also store unused calories in the forms of fats for later use by parking themselves in fat cells spaced between and among muscle and visceral cells.
Triglycerides can be made in the body via a variety of pathways. They most often seem to be synthesized from dietary carbohydrates (commonly in the liver), but can be imported more directly from the digestive breakdown of certain dietary fats.
Unfortunately, no matter whether home-grown or imported, excess circulating triglycerides can be metabolically transformed into larger and larger, harder-and-harder-to-break-down fatty deposits.
These are often found in blood vessels and termed atherosclerotic plaques. Dislodging these plaques, however, can be dangerous because they can travel through the blood stream and eventually block coronary or carotid arteries, leading to heart attacks and strokes, respectively.
In essence, the body’s other cells go from having a small tank of gas you could put into your trunk, to living in a highly congested neighborhood where most of the neighbors are gas stations.
In adults, triglyceride levels above 150 mg/dL are suspect, and levels above 200 mg/dL are now universally recognized as unhealthy. In addition to the cardiovascular consequences, they are strongly predisposing to the twin troubles of metabolic syndrome and adult onset diabetes.
Having too high a level of triglycerides is variously termed in the medical literature. Sometimes it is called hypertryglyceridemia, or more generally, dyslipidemia, and many articles lump studies of triglycerides with those of cholesterol levels using the umbrella term for the whole group, lipoproteins.
What disposes us to have too high triglyceride levels?
Historically, a number of factors seem to be associated in adult patients to overly high levels of triglycerides.
The most common in adults is obesity.
Next is diabetes.
A third is excessively low levels of thyroid hormones.
A fourth is kidney failure, particularly for patients on dialysis.
Somewhat rarer are pancreatitis and inherited diseases of triglyceride synthesis and metabolism.
Smokers, frequent drinkers of alcoholic beverages, people with high-blood pressure ------ and particularly those with high levels of low-density cholesterol are also much more likely to have high triglyceride levels.
Curiously, some vegetarian or near vegetarian diets high in rice and starches, have been implicated as well.
In recent years, four additional developments have also heightened awareness of high levels of triglycerides.
First, among adults, there is a now substantial population of HIV positive patients, who as a concomitant of the disease process or its antiretroviral medicines, are now living long enough to develop seriously high triglyceride levels with the risk of acute coronary artery disease. Literally hundreds of thousands of these patients will now likely die of heart disease before AIDS gets them.
Second, with an increased number of baby-boomers coming to an age where having prostate cancer is common, there is increasing worry that removal of the prostate and/or treatment with androgen blockers or feminizing hormones will have adverse effects on triglycerides.
Third, a debate has opened up as to whether or not high triglyceride levels should be attacked sooner than adulthood in the millions of kids who are already frankly obese (and particularly if they are already diabetic), and who, untreated, are perhaps likely to simply graduate into the adult complications of high levels of triglycerides.
Fourth, the hope for pharmaceutical leptins to control or modify triglycerides any time soon has largely waned.
General Strategies for Reducing Triglyceride Levels
The question then becomes, how best to bring down triglyceride levels?
While many of us are loathe to hear it once again, regular exercise of at least one half hour and arguably a whole hour, several times a week, has a good record of lowering triglycerides.
Weight loss, often as little as a 10% drop, yet another often claimed panacea for all of life’s adult ills, actually also proves to be highly effective in dropping triglycerides.
And boring as it is to hear, diet and exercise together work even better.
Conventional Pharmaceutical Treatment of High Triglyceride Levels
By far, the most common drug interventions in the U.S. to lower triglycerides involve the use of prescription strength niacin and one or more of the statins. (See, for example, Bays, 2008, cited below).
This combination has had fairly good results although certain forms of niacin may have cumulative liver toxicity in the long run, and liver function tests are recommended every six months.
Alternatively, particularly in Canada, and especially when dealing with diabetic patients, fibrate drugs are used. (See, for example, Barter & Ryle, 2006, Steiner, 2007, or Goldenberg, et al., 2009, cited below).
Commercial Nutritional Supplement Approaches to Lowering Triglycerides
Far less commonly recommended, and with substantially fewer articles in the literature to support taking them include larger doses of Vitamin D, increased intake of glucomannan and other sources of soluble fiber, and certain soy concentrates.
Dietary Ingredient Approaches to Triglyceride Level Reduction: Nuts and Fish
While a fairly wide variety of good dietary practices and food choices (eat more fruits and vegetables, prefer whole grains to refined ones, eat less red meat, etc.) are all recommended for the reduction of triglyceride levels, the two most common food items that are especially advisable are various nuts and fatty fish.
The literature in favor of certain tree nuts (particularly walnuts, hazelnuts, and pistachios) as agents for lowering triglycerides has been quite favorable.
Hopes for miracles from increased almond consumption have not yet been demonstrated in a very large scale clinical trial or via a rigorous meta-analysis , although many small studies are positive.
Cashews, macadamias, and even the usually despised Brazil nuts have their triglyceride-lowering supporters, although their studies basically show that eating them is not necessarily bad for blood lipid levels in healthy people, as opposed to their being uniformly reliable agents for triglyceride reduction.
It should be noted that in almost all these studies, funding was provided by nut producers, or the owners of companies whose products contain nuts.
Nonetheless, those studies were all conducted by independent labs at schools of nutrition or medicine, and appeared in refereed journals with a longstanding reputation for scientific integrity.
Fish whose tissues have high lipid levels, and are known to be good sources for omega-3 fatty acids, such as sardines, herring, mackerel, and salmon are also routinely recommended, as are over-the-counter supplements containing omega-3s.
But perhaps most promising along these lines is a new prescription strength omega-3 preparation, Lovaza. (see Dall & Bays, 2009, cited below), perhaps combining it with a statin. (see Davidson et al. 2007, and Barter & Ginsberg, 2008, cited below).
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