Older adults fear Alzheimer’s disease more than cancer. But how worried do you really need to be?

Let’s start with the good news…if you have a first-degree relative with the disease (a parent or sibling), you’re only at a slightly greater risk than someone who does not have a first-degree relative with Alzheimer’s. That’s because there are many factors that affect your risk for Alzheimer’s…not just your genes (more on this later).

Poor lifestyle choices (such as an unhealthy diet and/or not exercising regularly) also increase your risk—much more so than genetics. That’s why one twin in a set of identical twins can get Alzheimer’s while the other twin stays healthy.

There’s even more good news—a diagnosis of Alzheimer’s is not necessarily the disaster you probably imagine it to be. Alzheimer’s is now viewed by most medical professionals as a so-called “spectrum disorder,” rather than a single disease, because different people have different symptoms and different rates of progression.

Most people diagnosed with Alzheimer’s are not on the catastrophic end of that spectrum—they are not going to forget who they are or the names of their loved ones. Most will live at home and die at home, particularly if the disease is detected early and symptoms are well-managed with treatments such as medication, a healthy diet and regular exercise.

Bottom line: Even if you are at genetic risk, you can use lifestyle modifications to reduce your risk to below that of someone who has no family history of Alzheimer’s.

HOW TO TWEAK YOUR LIFESTYLE

Most cases of late-onset Alzheimer’s disease are preventable—with simple lifestyle changes that reduce one’s risk for the disease.

The brain changes of Alzheimer’s (the so-called plaques and tangles, which are accumulations of toxic proteins) can start 20 to 30 years before the onset of symptoms. But research shows that preventive measures can stop plaques and tangles as well as symptoms from ever developing…and even prevent symptoms if your brain is riddled with plaques and tangles.

Factors that increase Alzheimer’s risk for everyone—regardless of one’s genetic predisposition—and how to counteract them…

• Sedentary lifestyle. Exercising for 45 minutes, at least three days a week (at an intensity that is 50% higher than your resting heart rate) is a must for reducing your risk for Alzheimer’s. It stimulates blood flow to the brain, allowing new neurons to grow. Research shows that it decreases your risk for Alzheimer’s by 40%. Surprising fact: Cognitive abilities such as memory improve by 10% immediately after exercise.

• Poor diet. A diet loaded with saturated fats, refined sugar and processed foods increases the risk for Alzheimer’s. A Mediterranean-style diet—rich in whole foods such as vegetables, fruits, beans, whole grains and fish—is proven to reduce the risk for Alzheimer’s by 50%. Also helpful: A healthy breakfast, which consists of protein, fiber and fruit. Research shows that if you take in less than 7% of your daily calories at breakfast, your risk for heart disease and Alzheimer’s more than doubles.

• Limited mental stimulation. Regular mental stimulation reduces Alzheimer’s risk—in fact, research shows that even reading a newspaper every day can help prevent the disease. Best: Engage in a type of mental stimulation that is different from what you do at work, thereby stimulating a different part of your brain. Example: If you are a computer programmer, learn how to play golf.

• Social isolation. Healthy social relationships—with family, friends and in the community—decrease the risk for Alzheimer’s disease. Feeling lonely doubles the risk…living alone raises it fivefold.

• Heart disease. Circulatory problems cause heart disease and Alzheimer’s disease. Medical and lifestyle treatments for cardiovascular issues, including high blood pressure, reduce Alzheimer’s risk. Bottom line: What’s good for your heart is good for your brain.

• Diabetes. Some experts label Alzheimer’s “type 3 diabetes” because of the established link between chronically high blood sugar and the risk for Alzheimer’s disease—a person with diabetes has a 57% higher risk of developing the disease. Controlling high blood sugar with medical and lifestyle treatments is crucial for reducing Alzheimer’s risk. Helpful: Keep your glucose level below 100 mg/dL.

• Insomnia. Poor sleep increases risk for Alzheimer’s, probably because brain plaque is cleared most effectively during sleep. But sleep medications aren’t the answer—they also interfere with the clearance of brain plaque. What works better: Good sleep hygiene, such as going to bed and waking up at the same time every day. Also helpful: Don’t work on your computer in bed or keep your cell phone on your bedside table.

WHAT’S YOUR GENETIC RISK?

Genetics is a strong factor when Alzheimer’s begins at a young age. The early-onset form is an aggressive familial illness that can occur, in extremely rare cases, as early as in one’s 20s, with most people developing the disease in their 50s or 60s. The child of a parent with early-onset Alzheimer’s has a 50% chance of developing the disease. Fortunately, early-onset constitutes only 5% of all cases of Alzheimer’s disease.

On the other hand, most cases of late-onset Alzheimer’s (beginning after age 65) are not inherited. Instead, many medical and lifestyle factors contribute to the development of the illness.

Compelling scientific research: In one of the largest scientific studies that I have ever completed, published in Archives of Neurology, I looked at more than 5,500 siblings and parents of patients with Alzheimer’s—alongside age-matched adults who did not have the disease.

Presuming (for uniform statistical analysis) that everyone in the study lived to age 90, I found that those with a first-degree relative with Alzheimer’s had about a one-in-four chance of developing late-onset Alzheimer’s—whereas those without an afflicted relative had a one-in-five chance of doing so.

In other words, if neither your parents nor siblings have (or had) Alzheimer’s (and you live to age 90), you still have a 20% chance of getting the disease—while a person whose parent or sibling had Alzheimer’s has a 26% chance.

Takeaway: Having a parent or sibling with Alzheimer’s puts you at a relatively small increased risk for the disease. Exception: A person with late-onset Alzheimer’s who also has a variant of the apolipoprotein E gene—APOE e4 (the most damaging of the so-called “Alzheimer’s genes”)—is more likely to have rapid progression of the disease.

GENETIC TESTING

My take on genetic testing for Alzheimer’s: It may be appropriate only for people with a family history of early-onset Alzheimer’s disease (before age 65). If a parent has early-onset Alzheimer’s, as mentioned earlier, the child has a 50% chance of developing the disease. An estimated 200,000 Americans have the early-onset form of the disease.

If you have this type of family history, consult your doctor and a genetic counselor about genetic testing. Not all the genes that trigger early-onset Alzheimer’s are known, but some are. If you decide to have a genetic test—and the test finds that you have one of the genetic mutations for Alzheimer’s—you and your family can take that fact into account in various ways.

For example, you would want to create a step-by-step action plan for dealing with the disease, even before symptoms develop, by preparing for the future with advanced directives and financial planning…and perhaps consider entering one of the clinical trials that are testing new drugs to slow Alzheimer’s development. (To find such a trial, consult ClinicalTrials.gov and search “early-onset Alzheimer’s.”)

Important: If you don’t have a family history of early-onset Alzheimer’s, I typically do not recommend genetic testing. The results would not accurately quantify your risk, and it’s crucial that you implement key medical treatments (such as those for high blood pressure or diabetes) and lifestyle changes to reduce your risk for Alzheimer’s whether or not you have a genetic variant for late-onset Alzheimer’s.