Focus Family Nutrition on Current Health Needs

Q:  I am a mother of young children and I want to put nutritious food on our table. I've been reading about low-carb diets, the Mediterranean diet, and now even something called the "ape diet," and I can't sort out what's best. My husband has borderline cholesterol but otherwise we are all healthy.

Also, I am wondering about electrolytes. I have been told when my children are sick with a fever that I should replace their electrolytes with juices, crackers and water. What are electrolytes? How do they affect us?

A:  To answer your first question, the best diet for your family depends on your individual reasons for a dietary change, such as any medical conditions you need to address by improving your nutritional profile. If you are a healthy family with a simple goal to eat prudently, I like to recommend a diet that keeps the family happy so it is sustainable and encourages moderation.

High-quality scientific research on nutrition is difficult to carry out because people don't always stick to a prescribed diet and because people don't often accurately record their exact food intakes. Still, there are a few key principles that repeated research has borne out:

• Lots of fruits and vegetables are good. The fiber in fruits and vegetables has been shown to reduce cardiovascular disease, and the nutrients in fruits and vegetables have been shown to reduce cancer.
• Trans fatty acids and saturated fats are bad. These fats increase cardiovascular disease.
• Whole grains and high-fiber foods are good. Fiber reduces cardiovascular disease and diabetes.
• Pregnant women need folate supplementation to prevent birth defects such as spina bifida.
• Persons with inadequate dietary calcium, particularly postmenopausal women, need calcium supplementation to maintain bone strength.
• Above all, it is important to maintain a normal weight.

A low-carbohydrate diet such as the Atkins' diet may be an effective diet for weight loss, but you should check with your doctor before starting. It's difficult to maintain for the long term and it may not be appropriate for children.

The "Mediterranean diet" typically refers to a diet that is high in fruits, vegetables, bread, cereals, potatoes, beans, nuts, seeds and olive oil, moderate in poultry, fish, eggs and red wine, and low in red meat. The "ape diet" (a.k.a. "dietary portfolio") emphasizes plant sterols, soluble fiber, soy foods and almonds. Both these diets reduce cholesterol in people with high cholesterol and at risk for heart disease and some features (increasing fiber, fish and certain oils and nuts) are recommended by the American Heart Association for heart disease prevention even in people without heart or cholesterol problems.

To answer your second question, electrolytes are salts and other substances in body fluid that our vital organs need to function properly. Because they are charged particles, electrolytes that circulate in our blood set up a voltage gradient, like a battery, between cells for proper nerve and muscle function. Your heartbeat, for instance, is based on electrical impulses that require electrolytes.

Our main electrolytes are sodium, potassium, chloride, bicarbonate, sulfate, phosphate, calcium and magnesium. You may recognize sodium and chloride as the components of table salt; sodium is the positively charged particle, and chloride is the negatively charged particle. Sodium and chloride crystallize as salt when combined. The human body is able to maintain an appropriate balance of fluids, salts, minerals and other components by combining dietary elements with hormones and other substances that are produced internally.

Ordinarily the body has a large reserve of all electrolytes, and electrolytes are easily replaced without any special diet. However if you are sweating a great deal (either from athletic participation or with a fever) or if you have persistent vomiting or diarrhea, you will lose sodium and potassium. Usually these losses can be replaced with ordinary food and drink, such as the fluids and crackers you mentioned.

Sports drinks such as Gatorade contain electrolytes but are not necessary after a typical workout. For children who are exhausted or ill, drinks such as Pedialyte are recommended because they don't contain the large amounts of sugar that many of the sports drinks have.

Julie L. Mitchell, MD, MS, is an Assistant Professor of Medicine at the Medical College of Wisconsin. She practices internal medicine at the Froedtert & Medical College General Internal Medicine Clinic - East. Her column also appears in the Milwaukee Journal-Sentinel.