If you're like most Americans, you eat very few fruits and vegetables—for optimal health, the latest research calls for nine to 13 servings daily.

This dietary recommendation is linked to lower rates of serious diseases, such as cancer and heart disease, but few Americans learn about this from their doctors.

Why not? The most likely reasons are that few doctors receive training in how to counsel patients on nutrition, and office visits are often rushed. Issues your doctor may not discuss-or even know about…

Not Enough Vitamin D

Adults age 65 and older have a greater need for dietary sources of vitamin D. In younger adults, most vitamin D is synthesized in the skin following sun exposure. Older adults, however, usually spend less time in the sun. What's more, their ability to synthesize vitamin D from sunshine declines.

A vitamin D deficiency increases the risk for osteomalacia la condition that causes bone and muscle pain). Research shows that older adults who are vitamin D-deficient can improve muscle strength as well as reduce the risk for falls and fractures if they take a vitamin D supplement.

My advice: Get 1,000 international units (IU) of vitamin D-3 (cholecalciferol) daily from food and supplements. (Vitamin D-3 is the most potent form.)

Best food sources: Cold-water fish, such as salmon and mackerel, and milk.

Also: Get 10 to 15 minutes of sun exposure daily.

Inadequate B-12

A deficiency of vitamin B-12 is common in adults age 50 and older. It's usually due to an age-related decline in the production of gastric acid, necessary for vitamin B-12 absorption. Inadequate levels of vitamin B-12 can cause fatigue, loss of appetite and a form of anemia that, if not treated, leads to nerve damage and dementia.

A deficiency of folic acid (another B vitamin) can result in a similar type of anemia. If you take a folic acid supplement, it will correct the anemia but not if it is also due to a vitamin B-12 deficiency. In that case, your doctor may also prescribe a vitamin B-12 supplement.

My advice: Ask your doctor at least once a year for a blood test known as a complete blood count (CBC) to check for anemia. Specific blood tests to check for B vitamin deficiencies also may be recommended. In addition, tell your doctor about your diet, any supplements you take and your intake of alcohol, which can interfere with the absorption of many vitamins and minerals.

Gluten Sensitivity

Celiac disease occurs in people who react to gluten, a protein in wheat, barley and rye. Even trace amounts of gluten—in a single bite of bread, for example—can trigger the production of inflammatory chemicals, resulting in diarrhea, abdominal pain and/or bloating and other digestive symptoms.

Many celiac sufferers do not have the classic digestive symptoms of the disease. Instead, they may experience fatigue, headaches, and joint and muscle pain-symptoms doctors don't always associate with celiac disease.

My advice: If you have any of these symptoms and haven't been successfully treated, see an allergist or gastroenterologist. Ask about trying an elimination diet, in which all foods that contain gluten are completely avoided for two weeks. If you have celiac disease, symptoms usually will start to improve within that time.

Weight And Waist Size

Obesity is among the primary modifiable risk factors for high blood pressure, diabetes and many other medical problems. But not all doctors pay adequate attention to this important health issue.

Shocking statistic: In a recent study of 12,835 overweight or obese patients, 58% said that they had never discussed weight with a primary care provider. When doctors do give weight-loss counseling, it triples the odds that patients will attempt to lose weight.

My advice: Determine your body mass index (BMI), a commonly used standard that is more closely associated with body fat than is body weight alone. Aim for a BMI of 185 to 24.9 if you're age 65 or younger, and a BMI of 22 to 27 if you're age 66 or older. (A higher BMI is thought to help keep older adults healthy in the event of unintentional weight loss.)

Also, measure your waist circumference by wrapping a tape measure around your body at the midpoint between the tops of your hipbones and your lowest rib. (This point typically is at, or just below, the navel.)

*BMI is calculated by multiplying your weight (in pounds) by 703, then dividing that number by your height (in inches) twice. For a free, on-line BMI calculator, go to the National Heart, Lung and Blood Institute Web site (www.nblbisupport.com/bmi/).

More than 35 inches in women or 40 inches in men indicates a high proportion of abdominal fat, which greatly increases the risk for heart disease, diabetes and certain types of cancer—even in patients of normal weight.

If you need help losing weight or maintaining weight loss or could benefit from basic dietary advice—ask your doctor for a referral to a registered dietitian.

TV And Disease

Some doctors ask patients how much they exercise but rarely ask how much TV they watch. More than half of American adults watch more than two hours of TV daily-and even more on weekends.

Red flag: People who watch TV for more than two hours daily have an elevated risk for obesity, metabolic syndrome la constellation of symptoms, including abdominal obesity, low HDL "good" cholesterol and high blood pressure) and cardiovascular disease.

My advice: Limit TV viewing to less than two hours daily—and don't eat while watching TV. Studies show that people tend to eat more while watching TV.

Caution: Even if you don't watch a lot of TV, you can be at higher risk for disease if you have a sedentary lifestyle that involves many hours of sitting while working at a desk or computer, for example.

Want to Keep Reading?

Continue reading with a Health Confidential membership.

Sign up now Already have an account? Sign in