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A NitricOxide PrimerNitric oxide protects the heart, stimulates the brain, kills bacteria, stimulates blood flow to the kidneys, and has many other positive attributes within the body. Nitric oxide is a gas produced within cells throughout many parts of the body, the endothelial lining being one of them. Nitric oxide is able to diffuse through the cells and is quickly consumed close to where it is synthesized, thus exerting its effects in this area. Its primary function is to relax smooth muscle cells in the walls of the arterioles and inhibit the aggregation of platelets, thereby having an overall effect of improving blood flow and preventing the clotting of the blood. The cardio-protective effects of nitroglycerine hinged on the discovery that this medication releases nitric oxide in the body. The discoverers of nitric oxide were awarded a Nobel Prize in 1998. TOP
Summary Functions of Nitric Oxide in the Body
- Opens the coronary arteries that supply blood to the heart.
- A potent free radical scavenger that helps lower both serum cholesterol and prevent LDL cholesterol from oxidizing and becoming even worse.
- A powerful anticoagulant, or blood thinner, that helps prevent blood platelets from clumping together into clots that can cause a heart attack and stroke.
- A critical factor for proper immune function by eliminating foreign bacteria and viruses.
- Improves blood flow to the brain and may be involved in proper long-term memory function.
- Acts a messenger molecule that allows nerve cells in the body and the brain to communicate with each other.
- May reduce pregnancy related hypertension.
- May regulate insulin secretion by the pancreas, thereby reducing the risk of diabetes.
- Improves overall lung function
- Stimulates the body to release human growth hormone, a key to longevity as well as improvement in the body composition by boosting lean muscle mass and bone density while decreasing body fat tissue.
- Robert Fried, Woodson C. Merrell, James Thornton
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| Healthier Choices in Fast Food Restaurants |
| Arby’s Light Roast chicken Sandwich |
276 calories
7 gms of fat |
33 mg of cholesterol
777 mg of sodium |
| Burger Kings Chunky Chicken Salad |
276 calories
7 gms of fat |
33 mg of cholesterol
777 mg of sodium |
| Wendy’s Chili |
210 calories
7 gms of fat |
30 mg of Cholesterol
800 mg of Sodium |
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While the data are compelling to avoid high intakes of fast food, it is necessary to understand the common eating habits of Americans and how they are impacted by our everyday busy lifestyles. Perhaps the best and most appropriate advice is moderation, smart choices within these fast food outlets, and better nutrition at home. The opportunity for eating more fruits, vegetables, whole grains, and healthy fats such as monounsaturated and omega 3 oils becomes more imperative. The concept of healthy fats (monounsaturated and omega 3) have been well documented to improve conditions such as inflammation of the endothelial lining and atherosclerosis.
(See last newsletter for detailed mechanisms and discussion of these healthy fats)
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Fast Growing Problem
by Connie Guttersen, RD PhD,
author of the Sonoma Diet
Today's health professionals are faced with alarming statistics regarding the incidence of obesity, type II diabetes, and heart disease. Much of the concern stems from the common types of foods consumed as a result of our busy lifestyles: specifically, the large and frequent consumption of fast food. A study published (1) this year in the Journal of the American Medical Association concludes that Americans consume the largest portions at fast food establishments and the smallest at other restaurants. This study investigated nationally-representative data from the Nationwide Food Consumption Study Survey and the Continuing Survey of Food Intake by Individuals, a sample of approximately 60,000 individuals aged 2 years and older. The table below offers a descriptive summary of the actual increase in portion.
| Food Item |
Portion Size 20 years ago |
Recent Portion |
Change in Calorie Amounts |
| French Fries |
3.1 oz |
3.6 oz |
+68 Kcal |
| Mexican Food |
6.3 oz |
8 oz |
+133 kcal |
| Hamburgers |
5.7 oz |
7 oz |
+97 kcal |
| Soft Drinks |
13.1 oz |
19.9 oz |
+49 kcal |
Although this increase in calories may not appear to be large, on a yearly basis they may account to as much as a 3 to 5 pound weight gain. This is not surprising when one realizes that a 64 oz soft drink alone can provide as many as 800 kcal. TOP
Supersized Portions & Cardiovascular Risk
The factors driving the increase in portion sizes are not difficult to understand. From the consumers' perspective, larger portions at cheap prices are a bargain. Another study published this year in the Journal of The American Dietetic Association (2) also confirms an increase in portion sizes and suggests that when consumers are given larger portions they typically consume them. In addition, food portion sizes are positively related to energy intake in children and adults.
Recent medical studies are focusing on a broader perspective of cardiovascular risk factors, which go beyond looking at just blood cholesterol and tryglyceride levels. These intricate factors give a more detailed risk assessment and involve a better understanding of vascular biology and how it is impacted by the foods and fats we eat.
In recent years, it has become clear that the endothelium of the artery has many important functions in maintaining the integrity of the arterial system. How the endothelium functions is greatly related to the risk of developing inflammation and atherosclerosis. A healthy endothelium releases factors that are cardio-protective. Nitric oxide, for example, is a potent vaso-dilator. Other factors break up clots and platelets, inactivate free radicals, dissolve tryglycerides, and inhibit smooth muscle cell growth.
Normal vessel function depends critically on an intact endothelium. If the endothelium is not healthy or is considered to be dysfunctional, factors such as decreased nitric oxide production result in vaso-constriction and thrombosis. This condition changes the endothelium texture to one which is more narrow or constrictive and therefore apt to atherosclerosis and inflammation. Dr. Robert Vogel, professor of medicine at the University of Maryland Medical Center, described this condition as an endothelial lining with the texture of Velcro, thus promoting the condition of atherosclerosis. The concern for the intake of fast food is related to the large amounts of saturated fat and trans fatty acids. It is well documented that these types of fats are the most atherogenic, increasing the production of blood cholesterol and low density lipoproteins. TOP
After Meal Responses.
What has recently become of interest is the effect of fast foods on nitric oxide production within the body after the meal has been consumed (also referred to as the post prandial phase). Impaired vessel function is typically a precursor of atherosclerosis. To test the function of the inner wall of an arm artery in 20 healthy men and women, scientists Plotnick and Vogel used a blood pressure cuff to restrict blood flow for five minutes, then released the cuff. One minute later, they measured artery size using ultrasound. Normally, the vessel enlarges as the body tries to nourish areas that have been deprived. Individuals tested two hours after eating a fast food meal (approximately 900 calories and 50 gms of fat) consisting of eggs, sausage, biscuits, and hash browns had diminished vaso -dilation response for the next 4 hours. This result was due to a decreased amount of nitric oxide production within the endothelium. After high fat meals, fatty substances release free radicals and other oxidants, which are thought to deactivate the production of nitric oxide, thus hindering vaso-dilation. Further comments from Dr. Vogel at a recent American Dietetic Association Symposium (6) summarize the effects of eating a fast food breakfast with losing half of the amount of nitric oxide for 6 hours after the meal was consumed. When compared to the effects of smoking cigarettes, one cigarette removes all nitric oxide for 1-½ hours. In summary, he states, the effect of a child's fast food meal on nitric oxide production is the biological equivalent to smoking 2 cigarettes. Interestingly, in the same study by Plotnick and Vogel, antioxidants, such as 1000 mg vitamin C and 800 IU vitamin E, diminished the negative effects of the fast food upon nitric oxide production. Thus antioxidants may help keep blood vessels open, enabling healthy blood flow to the heart. Recent scientific data also indicate the negative effects of fast foods may produce even greater effects within individuals with diabetes. The effects of simple sugars, found in soft drinks in combination with fatty foods, further reduce the production of nitric oxide and the effect of vaso-dilation after a meal in combination with other factors that further damage the endothelial lining. TOP
| Nutritive Values of Common Fast Food Choices |
| Quarter Pounder with Large French Fries, 16 oz Soda |
| This meal |
Recommended Daily Intake |
| 1166 calories |
2000-2700 kcal |
| 51 gms fat |
50-80 gms fat |
| 95 mg cholesterol |
No more than 300 mg |
| 1450 mg sodium |
1100 to 3300 mg |
| 4 Slices of Sausage Mushroom Pizza, 16 oz Soda |
| This meal |
Recommended Daily Intake |
| 1000 calories |
2000-2700 kcal |
| 28 gms fat |
50-80 gms fat |
| 62 mg cholesterol |
No more than 300 mg |
| 2300 mg sodium |
1100 to 3300 mg |
| 2 Pieces of Fried Chicken (breast and wing), biscuit, mashed potatoes and gravy, corn on the cob, and 16 oz soda. |
| This meal |
Recommended Daily Intake |
| 1232 calories |
2000-2700 kcal |
| 57 gms fat |
50-80 gms fat |
| 157 mg cholesterol |
No more than 300 mg |
| 2276 mg sodium |
1100 to 3300 mg |
| 2 Pieces of Fried Chicken (breast and wing), biscuit, mashed potatoes and gravy, corn on the cob, and 16 oz soda. |
| This meal |
Recommended Daily Intake |
| 1057 calories |
2000-2700 kcal |
| 55 gms fat |
50-80 gms fat |
| 80 mg cholesterol |
No more than 300 mg |
| 1620 mg sodium |
1100 to 3300 mg |
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