Healthy Heart Diet

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Healthy Heart Diet

Research and general acceptance

Resources

Definition

A healthy heart diet is an eating plan designed to keep blood cholesterol low and prevent the risk of heart disease. This is usually achieved by eating foods that are low in saturated fat, total fat, cholesterol, and sodium . Some diets help people lower their cholesterol levels.

Origins

The healthy heart diet is the result of ongoing nutrition research by organizations including the United States Department of Agriculture (USDA) and the American Heart Association (AHA). The department first issued dietary recommendations for Americans in an 1894 Farmer’s Bulletin, according to the 1996 USDA report Dietary Recommendations and How They Have Changed Over Time.

The 1894 recommendations came from W.O. Atwater, first director of the USDA’s Office of Experiment Stations. He proposed a diet for American men based on protein , carbohydrate, fat, and mineral matter. In a 1902 Farmer’s Bulletin, he warned about the danger of a dieting consisting of too much protein or fuel ingredients (carbohydrates and fat). “The evils of overeating may not be felt at once, but sooner or later they are sure to appear—perhaps in an excessive amount of fatty tissue, perhaps in general debility, perhaps in actual disease,” Atwater cautioned.

More was known about nutrients in 1941 when the USDA first issued the Recommended Dietary Allowances (RDAs). The allowance allowances covered areas like calorie intake and nine essential nutrients: protein, iron, calcium, vitamins A and D, thiamin, riboflavin, niacin , and ascorbic acid (Vitamin C ). The USDA also released national food guides during the 1940s. The guides provided a foundation diet with recommendations for foods that contained the majority of nutrients. The guide was modified in 1956 with recommended minimum portions from food groups that the USDA called the “Big Four”: milk, meats, fruits and vegetables, and grain products.

The guides remained in effect until the 1970s when an increasing amount of research showed a relationship between the over-consumption of fat, saturated fat, cholesterol, and sodium and the risk of chronic diseases such as heart disease and stroke. In 1979, the USDA guide included the Big Four and a fifth category that included fats , sweets, and alcoholic beverages.

The following year, the USDA and the Department of Health and Human Services (HHS) issued the first edition of Nutrition and Your Health: Dietary Guidelines for Americans. The recommendations for healthy Americans age 2 and older included consuming a variety of foods, avoiding too much fat, saturated fat, cholesterol, and sodium. Those guidelines were recommended for people older than age 2 because younger children need more calories and fat in their diet to aid in their growth and development.

The USDA and HHS update the federal guidelines every five years. The 1990 edition recommended a diet low in fat, saturated fat, and cholesterol. Salt and sugars were to be consumed in moderation. In Dietary Guidelines for Americans 2005, the federal departments featured more specific recommendations.

The recommendations for healthy Americans came from two departments that are part of the National Institutes of Health (NIH). Within NIH is the National Heart, Lung, and Blood Institute (NHLBI), which was formed by Congress in 1948. In the 21st Century, the institute’s focus on heart disease included the creation of a Heart Healthy Diet to keep cholesterol low and the Therapeutic Lifestyles Changes (TLC) Diet to help people lower their blood cholesterol.

Furthermore, the American Heart Association (AHA)has long been concerned with educating the public about the relationship between diet and heart health. The association started in 1924 as an outgrowth of local organizations including the Association for the Prevention and Relief of Heart Disease in New York City. That group was founded in 1915 and consisted of physicians and social workers.

The national organization’s public education activities include issuing nutritional guidelines that are periodically revised. The title of the association’s “2006 Diet and Lifestyle Recommendations” reflected the importance of diet and physical activity on health,

Heart healthy diets

	Heart Healthy diet guidelines	Therapeutic Lifestyle Changes diet guidelines	American Heart Association diet guidelines
Saturated fat	8–10% of the day’s total calories	Less than 7% of the day’s total calories	Less than 7% of the day’s total calories
Total fat	30% or less of the day’s total calories	25–35% or less of the day’s total calories from fat	25–35% or less of the day’s total calories from fat
Dietary cholesterol	Less than 300 milligrams a day	Less than 200 milligrams a day	Less than 300 milligrams a day
Sodium	Less than 2,400 milligrams a day	Less than 2,400 milligrams a day	Less than 2,400 milligrams a day
Calories	Enough calories to achieve or maintain a healthy weight and reduce blood cholesterol level	Enough calories to achieve or maintain a healthy weight and reduce blood cholesterol level	Number of calories based on age, gender, height, weight, and physical activity level, and whether trying to lose, gain or maintain weight

A comparisonofthe dietary guidelines of the Healthy Heart diet, the Therapeutic Lifestyle Changes diet, and the American Heart Association diet . (Illustration by GGS Information Services/Thomson Gale.)

a combination endorsed by the medical community and public health organizations.

Description

Healthy heart diets share fundamental elements about how to prevent heart disease. The process starts with an understanding of why some foods should be avoided and others are beneficial to the heart. The first step is for the person to be aware of how food affects heart health.

An internal delivery system

The heart is a muscle, and the body’s muscles require a steady supply of oxygen and nutrients. This supply is brought to the heart by blood in the coronary arteries. Healthy heart diets are designed to keep the coronary arteries open for the delivery of oxygen and nutrients. When the arteries become narrow or clogged, the heart will not receive enough blood. This blockage causes coronary heart diseases. If the heart doesn’t receive enough of the blood containing oxygen, the person feels a chest pain, which is known as angina. If the coronary artery is totally blocked off and no blood reaches the heart, the person experiences a heart attack.

The narrowing or clogging of the arteries is designated as atherosclerosis when the blockage is caused by deposits of cholesterol and fat. Cholesterol is a soft, waxy substance that is similar to fats (lipids). Cholesterol occurs naturally and is found throughout the body in the bloodstream and cells.

Cholesterol’s functions

Cholesterol is used by the body to produce VitaminD , hormones, and the bile acids that dissolve food, according to NHBLI. However, the body doesn’t need much cholesterol to perform those functions, and the extra cholesterol is deposited in the arteries.

Cholesterol and fats don’t dissolve in the bloodstream and are moved through the body by lipoproteins. These are a combination of a lipid (fat) surrounded by a protein, according to the American Heart Association. Total cholesterol consists of low-density lipoprotein (LDL), high-density lipoprotein (HDL), and very-low density lipoprotein (VLDL).

VLDL carries triglycerides , a form of blood fat that could affect the heart. LDL is known as “bad” cholesterol, and HDL is called “good” cholesterol. HDL may help the body by clearing fat from the blood and removing extra cholesterol, according to the AHA.

The body produces LDL and receives more of it from food. When foods rich in cholesterol and some fats are consumed, the body creates more LDL. The dietary cholesterol comes from animal products such as meat. Also contributing to the LDL build-up are foods that are high in trans fats and saturated fats.

Fat facts

Food contains three types of fats that should be monitored on a healthy heart diet:

Saturated fat is the popular term for saturated fatty acid. Saturated fat tends to raise cholesterol levels and is found in meat, poultry, whole-milk dairy products including cheese and butter, cocoa butter, lard, and tropical vegetable oils like coconut and palms oils. Saturated fat remains solid at room temperature.

KEY TERMS

Body Mass Index —Also known as BMI, the index determines whether a person is at a healthy weight, underweight, overweight, or obese.

Calorie —The nutritional term for a kilocalorie, the unit of energy needed to raise the temperature of one liter of water by one degree centigrade at sea level. A nutritional calorie equals 1,000 calories.

Carbohydrate —A nutrient that the body uses as an energy source. A carbohydrate provide 4 calories of energy per gram.

Fat —A nutrient that the body uses as an energy source. Fats produce 9 calories per gram.

Fiber —A complex carbohydrate not digested by the human body. Plants are the source of fiber.

Morbidly obese —Also known as extremely obese, the condition of someone with a BMI of more than 40.

Obese —A person with a high amount of body fat; someone with a Body Mass Index of 30 or higher.

Overweight —A person is too heavy for his or her height; someone with a Body Mass Index of from 25 to 30.

Protein —A nutrient that the body uses as an energy source. Proteins produce 4 calories per gram.

Trans fat is a type of vegetable oil that was processed to make the liquid more solid. The process called hydrogenation produces hydrogenated and partially hydrogenated vegetable oils. These oils are found in stick margarine, vegetable shortening, commercial fried food, and baked goods such as cookies and crackers.
Unsaturated fats include polyunsaturated fats and monosaturated fats. Polyunsaturated fats are found in fish, walnuts, corn oil, and safflower oil. Mono-saturated fats are found avocadoes, olives, olive oil, canola oil, and peanut oil.

Sodium

Sodium and salt are sometimes used interchangeably in information about healthy heart diets. The AHA recommends that people consume less than 2,300 milligrams of salt per day. This amounts to about 1 teaspoon of salt. Some organizations recommend a slightly higher amount of less than 2,400 milligrams. The recommended amount is for healthy people and may be lower for people with some health conditions.

The diets of most Americans contain too much salt, and processed foods are generally the source of this sodium. A diet high in salt tends to raise blood pressure, and this could lead to heart disease, stroke, and kidney damage.

Reducing the amount of sodium in a diet will lower blood pressure, and aid in reaching healthy cholesterol levels. In addition, foods high in potassium counteract some of the effect of sodium on blood pressure, according to the USDA guidelines.

Creating a healthy heart diet

The federal government and the American Heart Association are among the organizations that provide recommendations for a healthy lifestyle. The recommendations frequently parallel those of the healthy heart diet, a plan that emphasizes the consumption of less fat, less cholesterol, and less sodium. There is also agreement that diets should include fiber-rich foods like fruits, vegetables, and whole-grain products.

Guidelines also focus on the importance of regular physical activity to prevent or lower the risk of conditions like heart disease. Generally, people are advised to exercise at least 30 minutes most days of the week. While some recommendations are designed for healthy people, the guidelines also apply to a healthy heart diet. There may be more specific instructions in plans to lower cholesterol levels.

DIETARY GUIDELINES FOR AMERICANS 2005 . Nutrition and Your Health: Dietary Guidelines for Americans defines a healthy eating plan as one that:

Emphasizes fruits, vegetables, whole grains, and fat-free or low-fat milk and milk products.
Includes lean meats, poultry, fish, beans, eggs, and nuts.
Is low in saturated fats, trans fats, cholesterol, salt, and added sugars.
The total fat intake should be between 20% to 35% of the daily calories consumed.

People can create a diet with those foods by using online tools like the USDA’s MyPyramid Plan and calculators on the NHBLI pages for the Heart Healthy and TLC diets. Someone Internet sites produce an individualized plan with specific calorie amounts, recommended foods, serving portions, and a system to track physical activity.

AMERICAN HEART ASSOCIATION 2006 DIET AND LIFESTYLE RECOMMENDATIONS . The heart association’s plan starts with the person determining how many calories are needed to maintain a healthy weight. People are advised not to eat more calories then they burn through activity. They should create a meal plan that includes:

A variety of vegetables and fruits and unrefined, whole-grain food.
Fish at least twice a week. Oily fish such as salmon, trout, and herring contain omega-3 fatty acids. These acids may help reduce the risk of fatal coronary disease.
Lean meats and poultry without skin. These proteins should be prepared them without added saturated and trans fat.
Less than 300 milligrams of cholesterol each day.
A moderate amount of alcohol, with one drink per day for women and two drinks per day for men.
Dairy products that are fat-free, 1% fat, and low-fat dairy.
Food containing little or no salt.
The association advises the public to cut back on:
Foods containing partially hydrogenated vegetable oils to reduce trans fat in their diets.
Foods high in dietary cholesterol.
Beverages and foods with added sugars.

The association certifies grocery products that meet the organization’s standards. Certification on packaging is indicated by a red heart with a white check mark inside. Products with that symbol meet association criteria for recommended amounts of saturated fat and cholesterol for healthy people above the age of 2. The standard-certification designation is based on one serving that contains 1 gram or less of saturated fat, 20 milligrams or less of cholesterol, and 480 milligrams or less of sodium. The wholegrains certification is issued to foods containing those quantities and an amount of whole-grain at a proportion of 51% by weight with reference to the amount customarily consumed.

THE NHBLI HEART HEALTHY DIET . The NHBLI website in the spring of 2007 featured heart healthy diet guidelines and an online tool to create a personal eating plan. The online activity starts with the person providing information about height, weight, gender, age, and level of physical activity. This action generates a recommendation for a daily calorie allowance. That allowance is used to determine the percentage of total fat and saturated fat permitted at that calorie level. The consumer then receives prompts to select food choices for three meals and a snack.

As information is received, the person sees the amounts of calories, fat, total fat, cholesterol, and sodium that would be consumed. After the final entry is made, the nutritional information is totaled. The total is compared with the recommended amounts. Along with that data are recommendations on how to modify the meal plan to lower fat and cholesterol consumption.

Meal planning on the heart healthy diet is based on these guidelines:

A person should eat just enough calories to achieve or maintain a healthy weight and reduce blood cholesterol level. A doctor or registered dietitian can determine what a reasonable calorie level.
Saturated fat should account for 8 to 10% of the day’s total calories.
Total fat should be 30% or less of the day’s total calories.
Dietary cholesterol should be limited to less than 300 milligrams per day.
Sodium intake should be limited to 2,400 milligrams a day.

THE TLC DIET . The Therapeutic Lifestyles Changes (TLC) Diet helps to lower the cholesterol of people who have a heart disease or at risk of developing one. The TLC section of the NHLBI contains online tools similar to those for the Healthy Heart diet. The guidelines for the low-saturated fat, low-cholesterol TLC diet are:

The person should eat just enough calories to achieve or maintain a healthy weight and reduce the blood cholesterol level.
Saturated fat should account for less than 7% of the daily total calorie total.
Fat consumed amounts to 25 to 35%% of the day’s total calories.
The person should eat less than 200 milligrams of dietary cholesterol per day.
Sodium intake should be limited to 2,400 milligrams per day.

Function

A healthy heart diet helps people age 2 and older reduce the risk of cardiac disease. This is achieved by the consumption of foods that keep total cholesterol and LDL cholesterol at healthy levels. A healthy heart diet may involve lowering cholesterol levels by reducing the amount of foods high in cholesterol, fat, and sodium. At the same time, people work to increase HDL levels through diet and exercise.

The healthy heart diet is a lifelong process that starts with education about the effects of food on the heart. People on this diet learn to make wise food choices, relying on information including the nutritional labels on processed food. The labels provide information about the calories, fats, sodium, and sugar in a single serving of the product.

Benefits

The benefits of a healthy heart diet are that people lower their cholesterol levels and reduce their risks of cardiovascular disease. A healthy heart diet is a preventive plan for people age 2 and older since high cholesterol could become an issue in childhood. Parents who place their children on healthy heart diets not only help them with physical health, they give their children with the basics for a lifetime of healthy habits.

Diet and regular physical activity keep cholesterol at healthy levels. The healthy heart diet that is also a weight loss plan will help obese and overweight people shed excess pounds. Smoking is another risk factor that will be lowered when people stop smoking. Diabetes and high blood pressure also put people at risk for heart disease. Both may be treated with medication, and people diagnosed with those conditions will benefit from a healthy heart diet.

Factors like heredity can’t be changed, so people with a family history of high cholesterol or early heart disease should prescribe to a heart healthy diet. The NHLBI defined the person at risk as someone with a father or brother diagnosed with this condition before the age 55. There is also a risk to someone with a mother or sister with this condition before age 65.

Furthermore, cholesterol levels rise as a person ages. The level rises in men at age 45 and older. For women, the increase is generally seen at age 55 and older, according to NHLBI.

Precautions

A healthy heart diet is safe for people age 2 and older. However, some people may to consult with their doctor before eating some foods such as fish. The United States Food and Drug Administration and the Environmental Protection Agency in 2004 warned pregnant women and nursing mothers to limit their consumption of fish and shellfish to 12 ounces (340.2 grams) per week. The warning was issued because of the risk that toxins in seafood would cause developmental problems in babies and children. Furthermore, women who are pregnant or nursing should not eat shark, marlin, and swordfish because of the high mercury content in these fish.

QUESTIONS TO ASK YOUR DOCTOR

Should I be concerned about my cholesterol levels?
What do I need to do to lower cholesterol levels?
Do I need to lose weight? If so, what is a healthy goal weight?
What healthy heart diet should I follow?
Should I avoid certain foods because of medications I’m taking or because of a health condition?
What is the minimum amount of calories that I should eat each day to lose weight?
Am I physically able to begin an exercise program?
What is the best type of exercise for me?
How long should I do this exercise?
How many times a week should I exercise?
Are there any instructions I need to prevent injuries?

Risks

When following a healthy heart diet, people need to be aware of the nutritional content of the foods they consume. They need to evaluate that information and make wise food choices. For example, the AHA points out that nuts and seeds are cholesterol-free sources of protein and a source of unsaturated fat. However, nuts and seeds are high in calories. Furthermore, frozen meals that are low in calories and fat should be examined for their sodium content.

Those foods can be part of a healthy heart diet. However, people need to observe nutritional recommendations for daily fat, sodium, and calorie allowances. Otherwise, their diet will aggravate a condition like high blood pressure or obesity .

Research and general acceptance

More than a century ago, W.O. Atwater of the UDSA cautioned about the dangers of overeating. His warning proved accurate. Cardiovascular disease (CVD) was the leading cause of death in the United States in each year since 1900, with the exception of 1918, according to the American Heart Association’s Heart Disease and Stroke Statistics—2007 Update. The heart association compiles that report in conjunction with government agencies.

According to the report, nearly 2,400 Americans die of CVD each day. That amounts to an average of one death every 36 seconds. In addition, an estimated 79,400,000 American adults (one in three) have one or more types of cardiovascular disease. Of those, 37,500,000 were estimated to be age 65 or older.

By the 1970s, research showed the link between chronic diseases like heart disease and stroke and a diet high in fat, saturated fat, cholesterol, and sodium. Research in the decades since then has affirmed the connection between poor diet and disease.

During those years, Americans ate more of the foods that put them at risk for heart disease. The average calorie consumption rose 16% between 1970 and 2003, according to USDA figures cited in the heart association report.

Information from the National Health and Nutrition Examination Survey for 1999-2000 indicated that Americans have not yet accepted the nutritional guidelines of a heart health diet. According to the report:

The average daily intake of total fat in was 79 grams, with men averaging 91 grams and women averaging 67 grams.
The average daily intake of saturated fat was 27 grams, with 31 grams for men and 23 grams for women.
The average amount of dietary fiber consumed was 15.6 grams, below the recommended amount of 25 grams or more. Men ate 17.8 grams of fiber and women consumed 13.6 grams.

In the 21st century, obesity in the United States is considered an epidemic. Federal agencies and organizations are responding with a range of programs to promote the benefits of a healthy heart diet.

Resources

BOOKS

American Heart Association. The new American Heart Association Cookbook. Clarkson Potter/Publishers, 2004.

ORGANIZATIONS

American Dietetic Association, 120 South Riverside Plaza, Suite 2000, Chicago, IL 60606. (800) 877-1600. <http://eatright.org>

American Heart Association National Center, 7272 Greenville Ave., Dallas, TX 75231. (800) 242-8721. < http://www.americanheart.org>.

WEBSITES

National Heart, Lung, and Blood Institute. Choosing Foods on the Heart Healthy Diet.<http://www.nhlbisup-port.com/cgi-bin/chd1/diet1.cgi> (April 21, 2007).

National Heart, Lung, and Blood Institute. Introduction to the TLC Diet. <http://www.nhlbi.nih.gov/cgi-bin/chd/step2intro.cgi> (April 21, 2007).

United States Department of Agriculture. MyPyramid Plan. <http://www.mypyramid.gov/mypyramid/index.aspx> (April 21, 2007).

OTHER

American Heart Association. American heart Association’s Heart Disease and Stroke Statistics— 2007 Update <http://www.americanheart.org/presenter.jhtml?identifier=1200026> (April 9, 2007).

Centers for Disease Control and Prevention National Center for Chronic Disease Prevention and Health Promotion. Physical Activity and Good Nutrition: Essential Elements to Prevent Chronic Diseases and Obesity At A Glance 2007. <http://www.cdc.gov/nccdphp/publications/aag/dnpa.htm> (April 9, 2007).

Davis, Carole and Sallo, Etta; U.S. Department of Agriculture Dietary Recommendations and How They Have Changed Over Time. <http://www.ers.usda.gov/publications/aib750/aib750b.pdf> (April 21, 2007).

U.S. Department of Agriculture and the Department of Health and Human Services. Dietary Guidelines for Americans 2005. <http://www.health.gov/dietaryguidelines/dga2005/document> (April 9, 2007).

Liz Swain.

The Gale Encyclopedia of Diets: A Guide to Health and Nutrition