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Metabolic FAQ

Frequently Asked Questions Regarding Metabolic Syndrome

July/August 2006

Metabolic FAQ: Frequently Asked Questions Regarding Metabolic Syndrome
In a follow-up to "Early Intervention for Metabolic Complications of HIV," which appeared in the March/April issue of Positively Aware, the authors answer some questions they are frequently asked about metabolic syndrome.

What is metabolic syndrome?

Metabolic syndrome, until recently known as Syndrome X, is a triad of metabolic abnormalities. The metabolic abnormalities are defined as high cholesterol, high blood pressure, and high blood sugar or insulin resistance. Patients with metabolic syndrome also have waist circumferences greater than 40 in. In HIV we use the term metabolic syndrome to refer to the same set of metabolic abnormalities.

What is insulin resistance?

Insulin is required for processing of blood sugar. Specifically insulin is used to get sugar from the blood into the cells where it is required for fuel (energy production.) The condition of insulin resistance opposes proper blood sugar control at the cellular level -- more insulin is needed to get sugar from the blood into the cell or the amount of insulin available over-regulates blood sugar control resulting in episodes of high blood sugar followed by low blood sugar levels.

What are ACE inhibitors?

ACE (angiotensin converting enzyme) inhibitors are a class of drugs that cause blood vessel widening (vasodilation) and are used to treat hypertension (high blood pressure) and heart failure. ACE inhibitors block the body's production of angiotensin, a vasoconstrictor (a chemical which stimulates constriction of blood vessels), and thereby improve the opening of blood vessels. ACE inhibitors help lower blood pressure and help protect the kidney by blocking this conversion to angiotensin. They are commonly used to treat symptoms associated with high blood pressure, diabetes, and HIV associated kidney disease (HIVAN).

What is HIVAN?

HIVAN is HIV-associated nephropathy (kidney problem). It is a syndrome causing loss of protein through the urine and decreasing renal (kidney) function. Proven clinical practice is to treat all diseases that may cause kidney problems, such as diabetes, and to intervene in HIV disease if a patient starts to develop HIVAN. ACE inhibitors are helpful in protecting the kidneys in diseases such as HIVAN.

Do all HIV-positive patients get metabolic syndrome and fat redistribution?

Not all HIV-positive patients experience metabolic and body composition changes. The occurrence of these complications is dependent on several factors. Most of the causes are not well understood. However, there are several studies that show associations with genetic predisposition, HIV itself, certain HIV medications, HAART (combinations of HIV medications), how long patients have been on HAART, the use of protease inhibitors and the lowest CD4 count. Fat redistribution is felt to be a syndrome of fat loss (lipodystrophy: sunken cheeks, skinny arms and legs) or fat accumulation (belly, neck and back fat). Lipodystrophy and lipoatrophy may or may not occur together. These characteristics are not always associated with metabolic syndrome. Proper nutrition and exercise have been shown to help prevent and ameliorate fat redistribution and metabolic syndrome.

Is my risk of heart disease increased because I have HIV?

Researchers think risk for heart disease is increased in HIV disease. The ongoing D:A:D trial shows a small but increased risk of heart disease associated with HIV disease. The trial is still early and the true increase in risk, or not, may be detected with ongoing monitoring. Our aggressive treatment of cardiac risk factors in HIV-positive patients is due in large part to this study and others like it.

What are the most potent nutritional strategies for optimizing metabolism and cotreating metabolic syndrome?

  1. Balance meals and snacks by including a source of protein, "good fat" and dietary fiber-rich carbohydrates.

  2. Especially, eat a protein and "good fat" containing breakfast.

  3. Eat over the course of the day avoiding long delays with meals.

  4. Try to include 4-6 small meals/snacks.

  5. Vary the types of good fat included with meals and snacks by getting a variety of olive, fish and flax types of oils and other foods containing these types of nutrients.

What laboratory tests do you use in your private practice to evaluate metabolism and medical nutritional status?

  • Chemistry panel

  • Complete Blood Count (CBC)

  • Lipid panel (Total-Chol, LDL-Chol, HDL-Chol, Triglycerides)

  • Hemoglobin A1C (HgA1C)

  • Thyroid Stimulating Hormone (TSH)

  • Free and total testosterone

  • 3 hour oral glucose tolerance test with insulin response to glucose (Insulin and glucose levels at time 0, 1, 2 ,3 hours)

In addition to published criteria (cut offs) for diagnosing metabolic syndrome, what other clinical indicators can help me understand my metabolism?

The following appear to be predictors of metabolic complications now or down the line:

  • Acne, skin or hair changes

  • Baldness, male pattern or hair thinning

  • Carbohydrate sensitivity or food cravings

  • Emotional issues such as depression, anxiety, forgetfulness or fogginess

  • Facial hair, increased (especially in women)

  • Family history of diseases such as diabetes, cardiovascular disease or symptoms, obesity, infertility

  • Fatigue/malaise

  • Insomnia

Also, blood sugar levels in the lower range of normal or a low HgA1c may be an indicator of insulin resistance or metabolic syndrome. Work with a clinician trained in evaluating the trend with laboratory measures of insulin and blood sugar measurements, and how these evaluations correlate to a physical exam and symptoms.

What is a glucose tolerance test?

A glucose tolerance test is a test that measures the body's response to glucose (sugar) after a period of fasting and over a certain amount of time after drinking a beverage that contains a measured amount of sugar.

The test is given in a lab or doctor's office in the morning before the person has eaten (usually after an eight hour fast). A first sample of blood is taken from the person at time point 0. Then the person drinks a liquid that contains a measured amount of glucose (sugar). Subsequent blood samples are taken at hours 1, 2, and 3. The object is to see how well the body deals with clearing blood sugar over time. Corresponding insulin levels can be obtained to gauge insulin response to glucose load. The test should be performed as described by WHO (World Health Organization), using a sugar load containing the equivalent of 75 g anhydrous (dry powder) dissolved in water.

What are proper blood sugar levels?

  • Fasting Plasma Glucose (FPG): <100 mg/dl

  • 2-h post load glucose: <140 mg/dl

What is hypoglycemia or low blood sugar?

The low end of normal for blood glucose is defined as 65 mg/dl. Often low blood sugar may not be regarded as clinically relevant. Ask again, especially when symptoms are present. In our office we look for tighter blood sugar control, i.e., FPG 85-95 mg/dl.

What are the criteria for diagnosing blood sugar abnormalities?

  1. Impaired fasting glucose or "prediabetes"

    • FPG 100-125 mg/dl

    • 2-h post load glucose 140-199 mg/dl

  2. Provisional diagnosis of diabetes

    • FPG >126 mg/dl

    • 2-h post load glucose >200 mg/dl

  3. Diagnosis of diabetes mellitus

    • Casual (any time of day without regard to meal time)

    • Plasma glucose >200 mg/dl plus symptoms of diabetes

What are the classic symptoms of diabetes?

Classic symptoms of diabetes include frequent urination (polyuria), excessive hunger (polydypsia) and unexplained, unintentional weight loss.

What are proper insulin levels?

In our practice we find that fasting insulin levels more than 5 micro IU/ml may be associated with symptoms of metabolic syndrome. Additionally, hours 1, 2, and 3 insulin levels may not appear unusual but when you evaluate these markers alongside of blood sugar levels and patient presentation, a story unfolds that points to sugar and insulin sensitivity as the root of metabolic complications. At our practice we have the input of a specially-trained endocrinologist to offer insights with possible medical co-therapies and understanding how to interpret the continually emerging set of data alongside metabolic syndrome and how the body processes sugar for fuel.

In order to conserve resources at medical clinics, which markers would you consider useful to screen for metabolic complications and insulin resistance?

  • Basic chemistry panel

  • Lipid profile

  • HgA1c

Most importantly, we also listen intently to our clients and use clinical presentation in structuring medical nutrition and lifestyle treatment options.

What is HgA1C?

HgA1C is a measure of how well blood glucose is controlled for the previous three to four months before the test. Glucose binds to hemoglobin (red blood cell) through a process called glycosylation. The higher the blood sugar the more glucose binds to the hemoglobin. This blood test measures the amount of glycosylation that has occurred revealing the average blood glucose levels.

Metabolic FAQ: Frequently Asked Questions Regarding Metabolic Syndrome
What is the target level for HgA1C?

The published normal range for HgA1C is 4% to 5.9%. The low end of normal for blood sugar is often overlooked as a clinical marker. Low HgA1C values may not be regarded as clinically relevant. Ask again, especially when symptoms are present. In our office we look for tighter control, i.e., HgA1C 5.2-5.7 mg/dl.

What is the difference, metabolically, between aerobic and resistive exercise?

Aerobic (with oxygen) exercise represents exercise with a low enough intensity to facilitate adequate oxygen transfer to the muscle cells so that no buildup of lactic acid is observed. This type of exercise may be useful for improving cardiovascular (heart) health, reducing insulin levels and lowering blood glucose. Anaerobic (without oxygen) is resistive exercise which includes weight training, weight machine use, and band workouts. Isometric or muscle building benefits are also realized with yoga, pilates and other forms of calisthenics.

Why is resistive exercise so important?

Resistance training will increase strength, muscular endurance, and muscle size, while running and jogging will not. Resistive exercise maintains and builds muscle which improves metabolism. Muscle burns stored body and blood fat more efficiently.

What is an adequate amount of dietary protein per day?

The daily requirement of protein is 0.8 to 1.5 grams per kg (1 kg = 2.2 pounds) of protein a day for healthy to moderately depleted adults. Dietary protein facilitates muscle building as part of a healthy diet and exercise plan. For individuals with renal (kidney) impairment, lower protein may be necessary.

Why are some fats "good" and some fats "bad" for you?

Good fats reduce insulin, inflammation and blood fat levels (olive, flax and fish oil types). "Bad fats" like chicken skin, bacon, visible meat fat, processed fats (trans and hydrogenated) increase blood fat levels and promote inflammation.

Is butter a "bad" fat?

In the debate over butter versus margarine, butter wins. Butter and other dairy products do contain saturated fat. We are advised to control our intake of saturated fat daily. It should be noted that the type of saturated fat contained in butter and other dairy is different that the saturated fat from chicken or meat skin.

What is the difference between butter fat and visible meat fat or chicken skin?

The difference between butter and other animal fat is the type and amount of saturated fat that these items contain. As a general rule, saturated fats are those fats that are hard at room temperature. Animal fat stays hard at room temperature, whereas butter fat softens. Butter is processed for fuel more efficiently than the type of fat found in chicken skin or visible meat fat. Also, about one-third of the fat in butter equals the type of healthy fat found in olive oil.

Given the upside to "good fats," can I eat as much as I want to?

Dietary fat is twice the caloric value of protein and carbohydrates. Overdoing fat intake can result in weight gain. It is also important to consider the health benefits of proper nutritional strategies and exercise with regard to maintaining a healthy weight.

What is the difference between simple and complex carbohydrates?

Simple carbohydrates are converted to sugar quickly and complex carbohydrates, usually containing higher fiber, convert to sugar more slowly.

What are the benefits of limiting sugar?

By limiting sugar and replacing refined carbohydrates (high glycemic value) with complex carbohydrates (high fiber, low glycemic value) the body is better able to process carbohydrate for fuel, providing a more efficient "burn" rate. Too much sugar at a given time gets converted to body fat or blood fat (i.e., cholesterol or triglycerides).

Does limiting sugar and refined carbohydrates mean that desserts or sweets are never allowed?

Desserts or sweets can be incorporated by reducing portion sizes. Avoid eating or drinking sugar-containing foods or beverages on an empty stomach. Increase exercise to maximize and maintain effective carbohydrate utilization.

What sweetener do you recommend?

In our practice we recommend Stevia. Stevia is a natural sweetener which is 400 times sweeter than sugar. There are other purported health benefits to Stevia including its role as an antioxidant and blood pressure-lowering agent. Stevia is not approved by the FDA as a sweetener, although it is available as a dietary supplement.

Why is skim milk higher glycemic than low-fat or whole milk?

Skim milk is a higher glycemic carbohydrate-containing beverage (more quickly converts to sugar) than low fat or whole milk because it lacks dietary fat. Fat acts to blunt blood sugar response after eating a carbohydrate containing meal.

Why are Corn Flakes or Cheerios high glycemic if there is not added sugar or a zero sugar value?

Although Cheerios and Cornflakes do not contain added sugar, they are rolled or processed, which results in the body converting these refined carbohydrates for fuel more quickly, causing a faster increase in blood sugar levels. These cereals are low in dietary fiber which may contribute to faster sugar uptake. Dietary fiber has a blood sugar-lowering tempering effect. Most cereals are high glycemic. Low glycemic cereals generally provide 8 g of fiber or more per 1/2 c serving. These include All Bran, Fiber One, Arrowhead Mills Steel Cut Oats, and Nature's Way Multi Bran Fiber.

Metabolic FAQ: Frequently Asked Questions Regarding Metabolic Syndrome
What are the clinical benefits versus potential side effects of Chromium?

Dose: The estimated safe and adequate daily dietary intake (ESADDI) for chromium is 50 to 200 micrograms daily.

Benefit: Chromium may have blood sugar-regulating activity. It may also lower cholesterol and reduce artery clogging activities.

How does Chromium work?

The mechanism of chromium's possible blood sugar regulation activity is not well understood. Chromium may enhance insulin activity and sensitivity. Chromium may improve the liver's role with insulin and blood sugar regulation. The mechanism of the possible cholesterol lowering activity of chromium is unknown. This effect may be due to the impact on blood sugar and insulin.

Potential side effects of Chromium

Chromium supplements are generally well tolerated. There are a few reports of bad reactions particularly with use of chromium picolinate. There is one report of a 24-year-old body builder who developed rhadomyolysis (muscle breakdown) after ingesting 1,200 mcg of chromium picolinate. A rare skin rash was also reported to be associated with the use of chromium picolinate. A case of interstitial nephritis (kidney problem) was reported to occur five months after a subject received a six-week course of 600 mcg chromium picolinate daily. Another report described anemia, thrombocytopenia, hemolysis (blood disorders,) liver and kidney problems and weight loss after the use of 1,200-2,400 mcg of chromium picolinate daily for four to five months.

What are the clinical benefits versus potential side effects of NAC?

Dose: Supplemental intake ranges from 600 milligrams once to three times daily. Those who supplement with NAC should drink 6 to 8 glasses of water daily in order to prevent renal (kidney) stones.

Benefit: N-acetyl cysteine (NAC) is a delivery form of L-cysteine, an amino acid (protein building block) which serves as a major precursor (building block) to the antioxidant glutathione. A major role of glutathione is the maintenance of liver health. Specifically, it is thought that NAC may protect cell membranes. NAC is also shown to reduce insulin levels and sugar uptake.

How does NAC work?

The effectiveness of NAC is due mainly to its activity as an antioxidant.

Potential side effects of NAC?

There are no reports of over dosage with oral, supplemental NAC. Adverse reactions reported with oral NAC include nausea, vomiting, diarrhea, headache (especially when used along with nitrates) and rashes. There are rare reports of kidney stone formation.

Why don't you recommend soy?

It seems like the jury is still out on the upside versus the downside of soy. Limited placebo-controlled trial data is available. Soy may have a negative effect on thyroid metabolism and other hormone balance, including proper insulin and estrogen metabolism.

Why do you suggest limiting whey-containing protein bars?

Some people have a hard time digesting milk proteins which include whey and casein.

Carla Heiser, M.S., R.D., L.D., is President and founder of Heiser & Associates, PC, The Center for Functional Nutrition. She received her nutrition training at the State University of New York College at Oneonta and Masters of Nutrition and Dietetics at New York Medical College (Valhalla, NY). Heiser worked under the auspices of leading cardiovascular and endocrine researchers at Columbia University (New York, NY) and Medlantic Research Institute (Washington, D.C.). She has 20 years of clinical nutrition and research experience.

Currently, she specializes in women's and men's health from a metabolic and hormone balance perspective. Blending nutrition with cutting-edge medical approaches to optimize health outcomes is a hallmark of her clinical practice approaches. She loves to cook and to make healthy food taste delicious. Teaching clients and colleagues is a passion as she continually strives to strengthen her skills. Heiser aspires to translate forward-thinking and research approaches into practical, "can do" strategies.

Dr. Tom Barrett is an HIV provider at the Howard Brown Health Center and Triad Health Practice in Chicago, Illinois. Barrett is on faculty at Northwestern University Medical School in Chicago and is primary investigator on several HIV associated research studies through Howard Brown Health Center.

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This article was provided by Positively Aware. It is a part of the publication Positively Aware. Visit Positively Aware's website to find out more about the publication.