Counseling Patients About Nutritional Issues

Every day, patients are bombarded with conflicting information about what constitutes a healthful diet. By focusing on patients' needs, risk factors, lifestyle, and eating habits, you can help them make the right choices.

In our article on page 171, we discussed strategies for motivating patients to make needed changes in their diet and general guidelines for preventive nutrition and weight loss. Here we offer specific advice for patients with hyperlipidemia, hypertension, diabetes, and the metabolic syndrome.

HYPERLIPIDEMIA

In 2000, 6.6 million physician office visits were made for cardiovascular disease (CVD).¹ The most cost-effective method of preventing CVD is lifestyle modification, which includes weight loss, physical activity, and dietary change. The most recent guidelines on such modifications can be found in the section "Therapeutic Lifestyle Changes" in the National Cholesterol Education Program's (NCEP) Third Adult Treatment Panel (ATP III) guidelines.² The primary dietary features of these guidelines include:

• Consuming less than 7% of calories from saturated fat.
• Keeping dietary cholesterol intake under 200 mg/d.

Because many patients are unaware of their daily caloric intake or of what percentage of that intake derives from saturated fat, it is important to translate the ATP III guidelines into actionable steps. Encourage patients to consume lean protein-rich foods, such as lean red meat, chicken, turkey, and fish, along with fresh fruits and vegetables. Instead of simply telling a patient to cut down on fat, identify sources of saturated fat and recommend foods that contain monounsaturated and polyunsaturated fats as replacements. Some examples of foods that contain saturated fat are butter, fat from meat, hydrogenated vegetable oil, cheese, chocolate, and fried foods. Common sources of monounsaturated fatty acids include olive oil, canola oil, peanut oil, nuts (walnuts, almonds, pecans, peanuts), and avocados.

When saturated fat intake is controlled, dietary cholesterol usually is reduced as well. In patients who succeed in keeping saturated fat intake under 7% of total calories, there is an approximately 8% to 10% reduction in low-density lipoprotein cholesterol (LDL-C) levels.^3,4 Keeping daily cholesterol intake under 200 mg/d can reduce LDL-C levels by 3% to 5% from baseline.^3,4 Be sure that patients are familiar with sources of dietary cholesterol. These comprise only foods that come from animals, such as meats, fish (primarily shellfish), poultry (dark meat and skin), egg yolks, and dairy products (full-fat versions). Point out that plant foods do not contain cholesterol.

trans-Fatty acids have gained attention over the past few years because of their adverse effects on blood cholesterol levels. They have been shown to raise LDL-C levels and, when consumed in relatively large quantities, may also lower high-density lipoprotein cholesterol (HDL-C) levels. The FDA now requires that all manufacturers list trans-fat content on food labels. trans-Fats are primarily found in baked and fried foods and in processed foods (such as salad dressings, cookies, crackers, and margarines) to prolong shelf life. A key term to look for on food labels is "partially hydrogenated."

Two types of functional food recommended by the NCEP for the management of hypercholesterolemia are plant stanols and sterols (also known as phytosterols) and viscous or soluble fiber. By interfering with the absorption of dietary and biliary cholesterol, plant stanols reduce LDL-C levels while maintaining HDL-C levels. Consumption of plant stanols has been shown to produce a 4% to 10% reduction in total cholesterol levels and a 6% to 14% reduction in LDL-C levels within 2 weeks.^5-7 The minimal amount required to produce a clinically significant reduction in the LDL-C level is 0.8 to 1 g/d.^5,7 The ATP III guidelines, the American Heart Association (AHA), and the American Diabetes Association recommend 2 g/d.^2,8,9 Encourage patients to incorporate plant stanols and sterols into their diet daily. Products that contain plant stanols/sterols or esters include spreads, yogurts, bars, and juices (Table 1).

The ATP III guidelines recommend 10 to 25 g/d of soluble fiber.

²

Soluble fiber can reduce LDL-C levels by 3% to 5% (

Table 2

). Soluble fiber is found in fruits, vegetables, cereal grains, dried beans, peas, and legumes, as well as in flaxseed, psyllium, and guar gum. Encourage patients to increase their intake of both soluble and insoluble dietary fiber. They can do this by choosing fresh fruit rather than canned fruit; eating whole-wheat products instead of those made of refined, white flour; eating a high-fiber cereal for breakfast; and increasing their consumption of vegetables at meals. Recommend looking at food labels and trying to consume products with 3 g or more of fiber per serving.

The ATP III guidelines estimate that the combined impact of its major dietary principles (reducing intake of saturated fat, reducing cholesterol intake, adding stanols/sterols, increasing intake of soluble fiber) could result in a 20% to 30% reduction in LDL-C levels (see Table 2). In addition, many studies have shown potential roles for nuts, omega-3 fatty acids, and soy protein in CVD risk reduction.

HYPERTENSION

The lifestyle and dietary modifications recommended for patients with hypertension include:

• Weight management.
• Adoption of the Dietary Approaches to Stop Hypertension (DASH) eating plan.
• Sodium restriction.
• Physical activity.
• Limitation of alcohol intake.

Table 3 summarizes the approximate reduction in systolic blood pressure that can be achieved with each of these interventions.

The average American consumes about 4000 mg of sodium daily. The current recommendation of the AHA¹⁰ and the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7)¹¹ regarding dietary sodium intake is no more than 2400 mg/d. Recently, the Institute of Medicine reduced the recommended daily allowance to less than 1500 mg.¹²

Some patients may think that they are sufficiently reducing their sodium intake by not adding salt to foods while cooking. Inform them that about three fourths of their sodium intake comes from processed and restaurant foods. Help them identify types of food that are high in sodium, such as processed foods, cured foods, foods packed in brine, and condiments. Advise them to rinse canned foods or purchase low sodium canned foods; use salt substitutes and season foods with herbs and spices; buy fresh meats, poultry, fish, eggs, and yogurt; and purchase whole foods (ie, those that consist of a single ingredient). Suggest that they aim for a sodium intake of less than 600 mg per meal.

The DASH guidelines are outlined in

Table 4.

The DASH and DASH-Sodium trials demonstrate the benefit of a comprehensive dietary approach for the prevention and treatment of hypertension.

¹³

The DASH eating plan has been shown to produce an 8 to 14 mm Hg reduction in systolic blood pressure.

¹⁴

The foods included in the eating plan are rich in magnesium, potassium, calcium, protein, and fiber and low in saturated fat, total fat, and cholesterol. The plan also promotes the consumption of whole grains, fish, poultry, and nuts.

The DASH eating plan is a combination approach that encompasses many suggestions. A practical way to advise patients regarding implementation of the plan is to suggest starting with 1 or 2 main goals. These might include:

• Aiming for 3 low-fat servings of dairy per day.
• Adding fruit to breakfast, lunch, and a snack.
• Eating a handful of unsalted nuts during the day.
• Including vegetables with every lunch and dinner (frozen vegetables are a convenient and acceptable alternative to fresh ones).

An awareness of serving sizes is important to ensure achievement of goals. For example, 1 cup of broccoli is equivalent to 2 servings of vegetables on the DASH plan, not 1. Note that the DASH eating plan, although rich in fruits and vegetables, was not designed for weight loss. If weight loss is needed, additional low-calorie foods, such as fruits and vegetables, should be used in place of the higher-calorie sweets and other foods allowed by the plan.

DIABETES

Diabetes is the sixth leading cause of death in the United States. Currently, about 7% of Americans--20.8 million persons--have diabetes; of these, nearly one third have undiagnosed disease.¹⁵ Lifestyle modification, which includes weight management and physical activity, is of utmost importance in the prevention and management of this disease. The key dietary recommendations for patients with type 2 diabetes are:

• To achieve and maintain a healthful weight.
• To plan meals consistently.
• To increase dietary fiber.
• To decrease total carbohydrates.
• To decrease saturated fat.

Strategies for weight loss are discussed in our article on page 171. A weight loss of 6% to 10% can significantly improve blood glucose management.¹⁶ Advise patients to eat at consistent times to avoid skipped meals and increased hunger, which often result in larger portion sizes and increased caloric intake. Recommend that patients go no longer than 4 hours without eating; if necessary, small snacks can be added between meals.

ATP, Adult Treatment Panel III; HDL-C, high-density lipoprotein cholesterol.

Adapted from the Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). JAMA. 2001.2

With carbohydrates, 2 factors are important: quantity and quality. Encourage patients to choose fruits and whole grains, as well as dairy products, as good sources of carbohydrates. These foods tend to have a higher fiber content, which can increase satiety and improve glycemic control. Strategies for increasing fiber include adding beans to salads, choosing a higher-fiber cereal at breakfast, and eating whole fruits and vegetables.

The glycemic index has attracted considerable attention in recent years as a guide to "good" carbohydrates; however, its value remains controversial. The glycemic index categorizes foods containing carbohydrates according to the extent to which they elevate blood glucose levels after consumption. However, the glycemic index value of a food applies only to the food eaten alone--not when consumed as part of a meal. Patients typically do not eat one food at a time, and eating foods in combination affects their glycemic index values in various ways. Thus, the glycemic index may be used as a tool for fine-tuning certain aspects of one's diet. However, there is insufficient evidence of the long-term benefits of following a low-glycemic index diet to recommend it as the principal basis for making food choices.¹⁷

METABOLIC SYNDROME

Insulin resistance, abdominal obesity, hypertension, and dyslipidemia are all characteristics of the metabolic syndrome. Diagnosis requires identification of 3 or more of the clinical findings listed in Table 5.

Management is first directed at treating the underlying individual components of the syndrome to prevent or delay the onset of diabetes, hypertension, and CVD. Initial prevention and treatment focuses on diet and exercise interventions. Dietary strategies appropriate for each of the components of the metabolic syndrome are described above. However, all aspects of the syndrome can improve with modest weight loss. In addition, even without weight loss, specific strategies to treat the other components of the syndrome can have a positive impact on health and reduce the risk of CVD.

References:

REFERENCES:

1.

Cherry DK, Woodwell DA. National Ambulatory Medical Care Survey: 2000 summary.

Adv Data.

2002;(328):1-32.

2.

Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. Executive Summary of the Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III).

JAMA.

2001;285:2486-2497.

3.

Jenkins DJ, Kendall CW, Axelsen M, et al. Viscous and nonviscous fibres, nonabsorbable and low glycaemic index carbohydrates, blood lipids and coronary heart disease.

Curr Opin Lipidiol.

2000;11:49-56.

4.

Carson JA, Burke FM, Hark LA.

Cardiovascular Nutrition: Disease Management and Prevention.

Chicago: American Dietetic Association; 2004.

5.

Hendricks HF, Westrate JA, Van Vliet T, et al. Spreads enriched with three different levels of vegetable oil sterols and the degree of cholesterol lowering in normocholesterolaemic and mildly hyper-cholesterolaemic subjects.

Eur J Clin Nutr.

1999;53:319-327.

6.

Davidson MH, Maki KC, Umporowicz DM, et al. Safety and tolerability of esterified phytosterols administered in reduced-fat spread and salad dressing to healthy adult men and women.

J Am Coll Nutr.

2001;20:307-319.

7.

Hallikainen MA, Sarkkinen ES, Uusitupa MI. Plant stanol esters affect serum cholesterol concentrations of hypercholesterolemic men and women in a dose-dependent manner.

J Nutr.

2000;130:767-776.

8.

Pearson TA, Blair SN, Daniels SR, et al. AHA Guidelines for Primary Prevention of Cardiovascular Disease and Stroke: 2002 Update. Consensus Panel Guide to Comprehensive Risk Reduction for Adult Patients Without Coronary or Other Atherosclerotic Vascular Diseases. American Heart Association Science Advisory and Coordinating Committee.

Circulation.

2002;106:388-391.

9.

Franz MJ, Bantle JP, Beebe CA, et al; American Diabetes Association. Evidence-based nutrition principles and recommendations for the treatment and prevention of diabetes and related complications.

Diabetes Care.

2003;26(suppl 1):S51-S61.

10.

Krauss RM, Eckel RH, Howard B, et al. AHA Dietary Guidelines: revision 2000. A statement for healthcare professionals from the Nutrition Committee of the American Heart Association.

Circulation.

2000;102:2284-2299.

11.

Chobanian AV, Bakris GL, Black HR, et al; National High Blood Pressure Education Program Coordinating Committee. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure: the JNC 7 Report.

JAMA.

2003;289:2560-2572.

12.

Institute of Medicine of the National Academies. Report on Dietary Reference Intakes: Water, Potassium, Sodium, Chloride, and Sulfate. February 11, 2004. Available at: http://www.iom.edu/ report.asp?id=18495. Accessed December 15, 2005.

13.

National Heart, Lung, and Blood Institute.

Facts about the DASH Eating Plan.

Bethesda, Md: National Institutes of Health; 2003. NIH publication 03-4082. Available at: http://www.nhlbi.nih.gov/health/ public/heart/hbp/dash/new_dash.pdf. Accessed December 15, 2005.

14.

Appel LJ, Moore TJ, Obarzanek E, et al. A clinical trial of the effects of dietary patterns on blood pressure. DASH Collaborative Research Group.

N Engl J Med.

1997;336:1117-1124.

15.

American Diabetes Association. All about diabetes. Available at: http://diabetes.org/ aboutdiabetes.jsp. Accessed December 15, 2005.

16.

Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults--The Evidence Report.

Obes Res.

1998;6(suppl 2):51S-209S.

17.

Franz MJ, Bantle JP, Beebe CA, et al. Evidence-based nutrition principles and recommendations for the treatment and prevention of diabetes and related complications.

Diabetes Care.

2002;25:148-198.