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Hyperlipidemia
 

Hyperlipidemia Introduction

The term hyperlipidemia signifies high lipid or fat content in the blood. Most people are familiar with having high cholesterol, but hyperlipidemia could also refer to having high amounts of triglycerides, phospholipids, or other fats in the bloodstream. Hyperlipidemia may be caused by genetic factors, as in certain familial diseases. It may also be caused by secondary factors like certain dietary influences, especially in acquired hyperlipidemia. It is important to consider what the health implications of hyperlipidemia are, and separate out what causes high levels of fat to be harmful. Individuals at at increased risk of development must understand both the necessity ,and appropriate types and amounts of dietary fats.

Cholesterol is a critical molecule. We get cholesterol from endogenous sources, meaning that we produce it. We also derive cholesterol from those exogenous sources food we eat, namely, meat, poultry, eggs and dairy products. It is important to note that cholesterol only comes from foods made from animals. Produced in the liver, it provides for many critical roles in human physiology. Cholesterol is considered the starting building block for our hormones, assists in the formation of integral cellular membranes, and is one of the main substances that the brain is made from. Therefore, we need the right amounts of this substance to maintain optimal function.

Because cholesterol and other fats can’t dissolve in the blood, special carriers known as lipoproteins transport the fats between cells. These carriers are known as chylomicrons, and include; low-density lipoproteins (LDL), intermediate-density lipoproteins (IDL), high-density lipoproteins (HDL), and very low-density lipoproteins VLDL. [1] Of most clinical importance are the low-density, and high-density lipoproteins, or LDLs and HDLs. LDLs are also known as the “bad” cholesterol and high-density lipoproteins, or HDLs, are known as the “good” type of cholesterol.

  • LDL cholesterol is responsible for transporting fats form the liver to body cells. In excess they can accumulate in the arteries, increasing the risk of heart attack and stroke.
  • HDL cholesterol on the other hand, carries cholesterol back to the liver and is shown to be protective against the abovementioned diseases.

It should be understood that cholesterol in isolation isn’t the problem. Cholesterol becomes problematic when it becomes oxidized by free radicals, often leading to a cascade of events that eventuates in plaques in the arteries.

Triglycerides are the most common dietary fats, and are the main component of vegetable oil and animal fat. They are comprised of fatty acids with an esterified glycerol backbone, and are essential for producing some of the energy that our cells depend on for their functioning. During the digestive process, triglycerides are split into specialized components, travel to the blood stream where they are reassembled into constituents of lipoproteins. Various tissues store these packages, which are broken down as necessary for energy production.

A high level of triglycerides in the blood is known as hypertriglyceridemia, a subset of hyperlipidemia. The health implications of this state are related to an increased risk of atherosclerosis (hardening of the arteries), and by extension, heart disease, and stroke. In addition, there is a strong inverse relationship between high triglycerides and low HDL. the condition of high triglycerides is often paralleled by low HDL, setting one up for negative health consequences.

Other markers related to increased risk of heart disease and strokes are the apolipoprotein A1 (Apo A1) and B (Apo B). Apolipoproteins are a combination of lipid and protein that function with the lipoproteins. Specifically, Apo A1 is primarily found in HDL cholesterol, while Apo B makes up a large percent of LDL cholesterol. Subsequently, their ratio is a convenient marker for assessing atherosclerotic risk. Other markers such as lipoprotein A, C-Reactive Protein (CRP), the amino acid homocysteine, along with diet, lifestyle, age, family, history health history, all contribute to a comprehensive assessment of one’s cardiovascular risk.

Hyperlipidemia Symptoms

Symptoms of hyperlipidemia don’t really exist. Unfortunately, if not detected early, the end result of high levels of fat in the blood could be heart disease, stroke, pancreatitis, or other chronic diseases. What’s even more alarming is that the first signs of these diseases are of the event itself, such as a heart attack or stroke. Fortunately, prevention of these conditions can be achieved by regular lab testing to determine levels of cholesterol and triglycerides as well as other risk factors. Assessment of one’s risk enables at risk individuals to seek treatment and ward off further complications, and to engage in preventative measures to avoid the more serious consequences. Conditions that increase risk for hyperlipidemia include;

  • Diabetes Mellitus (non-insulin dependent and insulin dependent)
  • Cushing’s Syndrome
  • Certain types of renal (kidney) disease
  • Diet high in saturated fat (fried foods)
  • Sedentary lifestyle
  • Cigarette smoking
  • Excessive alcohol consumption
  • Medications such as beta blockers, diuretics and birth control pills

Hyperlipidemia Statistics

  • The percent of adults age 20 years and older with high serum levels of cholesterol was 17% of the population (based on the years 1999 to 2002).
  • The average serum cholesterol level for adults’ age 20 years and over: 203 mg/dL (1999-2002).
  • Percent of visits to office-based physicians with cholesterol measure ordered or provided: 5.2 (2002) [2].
  • Approximately 105 million American adults have total blood cholesterol levels of 200 milligrams per deciliter (mg/dL) and higher. Of these, 42 million have levels of 240 mg/dL or higher, which is considered high risk. [3]

Hyperlipidemia Treatment

Conventional treatment for hyperlipidemia speaks to dietary manipulation and exercise, and when this isn’t enough to lower blood levels to a ‘safe’ level, drug treatment is often initiated. Common drugs known as statins are employed to block cholesterol production in the liver. Side effects of these drugs include nutrient depleting effects, such as Co-Q10, which can have negative ramifications on the heart.

Other medications target cholesterol breakdown, which is another mechanism that assists the liver in the removal of cholesterol from the blood. However, these therapies are often only given a limited time to work, and at times, patients are fast tracked for surgical procedures which remove plaques. These individuals are, however, often marked by an underlying disability and typically have a fast return to pre-surgical blockages within a few months.

Supplements helpful for Hyperlipidemia

Flaxseeds

Flaxseeds are a source of omega 3 essential fatty acids, soluble fiber, and lignans, which help to balance out estrogen levels. The role of flax seeds in atherosclerosis is related to its ability to reduce platelet aggregation, lower blood cholesterol, and process excess bile acids via its fiber component.

In a study utilizing laboratory animals, supplementation with flaxseeds seemed to decrease hypercholesterolemic atherosclerosis without decreasing serum cholesterol, implicating flaxseeds as beneficial supplement for lowering heart attack and stroke risk related to hypercholesterolemia. [4]

Other research also validates the lipid lowering effects of flaxseeds. In a study with 15 subjects with high blood cholesterol levels, supplementation with flaxseeds decreased total and LDL- cholesterol by approximately 10%, as well as significantly reducing platelet aggregation. In addition, participants maintained positive HDL cholesterol and triglyceride levels. [5]



Fish Oil (EPA/DHA)

Essential fatty acids, such as EPA and DHA, are beneficial for a number of reasons. They play a critical role in body function and structure, such as regulating steroid production and hormone synthesis, dilation and constriction of blood vessels, preventing blood cells from clumping together (clotting), and are primary constituents of cellular membranes. [6]

Many studies implicate the cholesterol lowering effects of fish oils. Questions arise as to whether one should supplement with fish oil or just consume more fish in the diet. Research suggests that increasing fish in the diet may not have a similar protective effect to that oil supplementation, but both showed a positive response in preventing atherosclerotic plaque. A study involving 25 men over a five-week period of time showed that both fish oil and the same amount of oil ingested in whole fish form, lowered triglycerides and raised HDL cholesterol levels. [7]

Vitamin E

Vitamin E is well known for is antioxidant capacity and plays a major role in the prevention of heart disease and strokes. It has the ability to reduce LDL cholesterol oxidation, decrease excessive amounts of platelet aggregation, and provide an increase in HDL cholesterol and fibrinolytic activity. [8]

A study involving 156 men, ages 40 to 59 with a previous history of coronary bypass graft surgery, exhibited less adverse symptoms of coronary artery progression when supplementing with 100 IU or more of vitamin E. This finding was compared to the another test group which was supplemented with less than 100 IE of vitamin E. [9]

Fiber

Water-soluble gels and mucilaginous fibers, such as oat bran, can decrease lipid content in the blood by increasing its removal through the bowel, and preventing its manufacture in the liver. Whole oat products are more beneficial in decreasing total cholesterol and LDL cholesterol levels than consuming products with oat bran and beta-glucan fiber combined. [10]

Psyllium

Blond psyllium also shows effectiveness in reducing cholesterol levels in those with high cholesterol levels. With supplementation, it can reduce total cholesterol levels between 3-14%, LDL cholesterol by 5-10%, and apolipoprotein B by 8.8%. After extended treatment, if may also significantly reduce the LDL: HDL ratios. [11, 12]

Niacin

Niacin, or vitamin B3, functions in the body as a component of the compounds NAD and NADP, both of which are involved in over 50 chemical reactions throughout the body. Niacin plays an important role in fat, cholesterol and carbohydrate metabolism, hormone production, and energy production.

Niacin’s lipid lowering ability translates into a reduction of LDL and VLDL cholesterol blood triglycerides and lipoprotein A. In addition, it has also been shown to increase HDL cholesterol. [13] The benefit of this supplement seems to be dose dependent; higher doses have more of a profound effect, but low dose has shown to be of some value as well. It is well known that niacin is not without side effects. The most well known reactions being skin flushing, gastric irritation, nausea, and possible liver damage.

Inositol hexaniacinate is the safest form of niacin available, and greatly reduces the ill effects of niacin; but because it is metabolized to niacin, there is still the risk of mild side effects. [14] Before supplementing with niacin, one should consult with their physician due to the probability of developing serious side effects with an elevated dosage.

Guggul (Commiphora mukul)

Guggul is an Ayurvedic remedy made from the gum resin of the Commiphora mukul tree native to India. Within the extracts, compounds such as the ketonic steroids, Z-guggulsterone and E-guggulsterone are found. These compounds are suspected to inhibit the synthesis of cholesterol in the liver and also provide for an antioxidant effect on lipids. [15, 16]

Studies involving both animals and humans have validated the theory that guggul has a lipid lowering effect. This effect is thought to be related to its ability to influence cholesterol balance by acting as a bile acid receptor agonist. [17] Although some research is contradictory to the positive effects of guggul, this herb has been used for over 2000 years for hyperlipidemia. [18]

Garlic (Allium Sativum)

Garlic has been used effectively for its purported medicinal properties for centuries around the world. The active compound in garlic, allicin, is released from the cloves when crushed. Garlic has been touted for its cardiovascular protective effects, and has been shown to be effective at reducing the risk of heart disease and stoke, by lowering total cholesterol, LDL cholesterol, and triglycerides, without adversely affecting HDL Cholesterol. [19, 20] Garlic also increases fibrolytic activity and platelet aggregation through the breakdown products of allicin. This is extremely important in preventing the formation of atherosclerotic plaques. [21]

Red Yeast Rice

Red Rice Yeast is produced by the fermentation process of rice with Monascus purpureus yeast. The product is produced in a controlled environment to increase the amount of mevinic acids, which in essence, block the metabolism of cholesterol. The principle active constituent of red yeast is mevinic acid, in which lovastatin is found. These compounds act as HMG-CoA reductase inhibitors; or in other words, they act to block the biosynthesis of cholesterol. [22]

In a study involving 83 subjects with hyperlipidemia, supplementation with red yeast rice significantly reduced total cholesterol, LDL cholesterol, and total triacylglycerol concentrations without significantly altering HDL cholesterol levels. Researchers concluded that due to these results, red rice yeast provides a food-based approach to treating hyperlipidemia. [23]

References

[1] Understanding the Essentials of Blood Lipid Metabolism. Prog Cardiovasc Nurs 18(1):13-18, 2003. © 2003 Le Jacq Communications, Inc

[2] National Ambulatory Medical Care Survey: 2002 Summary http://www.pdrhealth.com/drug_info/nmdrugprofiles/herbaldrugs/101840.shtml

[3] CDC’s National Center for Health Statistics as published by the American Heart Association, Heart and Stroke Statistics — 2003 Update. Dallas, TX: AHA, 2002

[4] Prasad K, Dietary flax seed in prevention of hypercholesterolemic atherosclerosis. Atherosclerosis. 1997 Jul 11;132(1):69-76.

[5] Bierenbaum ML, Reichstein R, Walkins T. Reducing atherogenic risk in hyperlipemic humans with flax seed supplementation: a preliminary report. J Am Coll Nutr 1993;12:501–4

[6] Murray, Michael T, Encyclopedia of Nutritional Supplements: Understanding fats and oils, Pg 237-248 © Prima Publishing 1996

[7] Cobias L, et al., Lipid, lipoprotein, and hemostatic effects of fish vs fish oil w-3 fatty acids in mildly hperlidemic males. Am J Clin Nutr 53, 1210- 1216, 1991

[8] Murray, Michael T, Encyclopedia of Nutritional Supplements: Vitamins, Pg 49 © Prima Publishing 1996

[9] Hodis HN, et al., Serial coronary angiographic evidence that antioxidant vitamin intake reduces progression of coronary artery atherosclerosis. JAMA 273 1849-1854, 1995

[10] Kerckhoffs DA, Hornstra G, Mensink RP. Cholesterol-lowering effect of beta-glucan from oat bran in mildly hypercholesterolemic subjects may decrease when beta-glucan is incorporated into bread and cookies. Am J Clin Nutr 2003;78:221-7.

[11] Anderson JW, Allgood LD, Lawrence A, et al. Cholesterol-lowering effects of psyllium intake adjunctive to diet therapy in men and women with hypercholesterolemia: meta-analysis of 8 controlled trials. Am J Clin Nutr 2000;71:472-9.

[12] Bell LP, Hectorne K, Reynolds H, et al. Cholesterol-lowering effects of psyllium hydrophilic mucilloid. Adjunct therapy to a prudent diet for patients with mild to moderate hypercholesterolemia. JAMA 1989;261:3419-23.

[13] DiPalma JR and Thayer WS, Use of Niacin as a drug. Annu Rev Nutr 11, 169-187, 1991

[14] Anon. Inositol hexaniacinate. Altern Med Rev 1998;3:222-3.

[15] Singh RB, Niaz MA, Ghosh S. Hypolipidemic and antioxidant effects of Commiphora mukul as an adjunct to dietary therapy in patients with hypercholesterolemia. Cardiovasc Drugs Ther 1994;8:659-64.

[16] Panda S, Kar A. Gugulu (Commiphora mukul) induces triiodothyronine production: possible involvement of lipid peroxidation. Life Sci 1999;65:PL137-41.

[17] Nancy L. Urizar and ­David D. Moore, GUGULIPID: A Natural Cholesterol-Lowering Agent. Annual Review of NutritionVol. 23: 303-313

[18] Szapary PO, Wolfe ML, Bloedon LT, Cucchiara AJ, DerMarderosian AH, Cirigliano MD, Rader DJ. Guggulipid for the treatment of hypercholesterolemia: a randomized controlled trial. JAMA. 2003 Aug 13;290(6):765-72.

[19] Warshafsky S, Kramer RS, Sivak SL. Effect of garlic on total serum cholesterol: a meta-analysis. Ann Intern Med 1993;119:599–605.

[20] Kleijnen J, Knipschild P, ter Riet GT. Garlic, onions and cardiovascular risk factors. A review of the evidence from human experiments with emphasis on commercially available preparations. Br J Clin Pharmacol 1989;28;535–44

[21] ibid

[22] Robbers JE, Tyler VE. Tyler’s Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York, NY: The Haworth Herbal Press, 1999.

[23] Heber D, Yip I, Ashley JM, Elashoff DA, Elashoff RM, Go VL, Cholesterol-lowering effects of a proprietary Chinese red-yeast-rice dietary supplement. Am J Clin Nutr. 1999 Feb;69(2):231-6.