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The Link Between Carbohydrates, Insulin, and Alzheimer’s

Fruit and vegetable salad and glucose meter with tape measure


We know that a diet high in starchy foods can lead to diabetes and heart disease. Starchy foods are carbohydrates. Some studies show that this food group also may be linked to mild cognitive impairment (MCI). MCI may be an early form of Alzheimer’s disease. MCI does not always lead to Alzheimer’s, though.

A recent study by the Mayo Clinic found that older people who ate a diet high in starchy foods were four times more likely to develop MCI. Eating a diet high in sugar increases the risk. The study also found that eating lean proteins and fats from healthful sources helped to keep the brain healthy.  

Researchers still do not know what causes Alzheimer’s. Cognitive decline can be caused by many things. It is still a good idea to take a look at your diet and try to eat foods that can help keep your brain and body healthy.

The Importance of Insulin

Insulin is a hormone the body uses for many functions. One function is to keep brain cells healthy. 

Foods that contain carbohydrates, or carbs, raise blood glucose levels (glucose is a type of sugar). There are two types of carbs. Complex carbs take longer to digest. They cause blood sugar to rise slowly. Refined or simple carbs are digested quickly. They cause blood sugar levels to go up very quickly. Eating a diet that is high in refined carbs could lead to insulin resistance over time.

Insulin resistance is when cells stop responding to insulin. When this happens, our bodies make more insulin. Insulin resistance can lead to type 2 diabetes. With Alzheimer’s, parts of the brain become resistant to insulin. In fact, those with diabetes are twice as likely to develop  Alzheimer’s.

Balance Your Plate

Good sources of complex carbs are vegetables, fruits, dried beans and whole grains. These foods provide your body with energy. They contain fiber, vitamins and minerals. Refined carbs are those from sugar (even honey), fruit juices, white bread, white rice, pastries, sodas, and processed foods.

To keep your brain healthy, avoid refined carbs and add healthy fats and proteins. Think of the proportions of your plate. Half should be filled with non-starchy vegetables like salad greens, broccoli, or bell peppers. One fourth should contain a heart-healthy protein like salmon, skinless chicken, turkey burger, lean beef or pork with the fat trimmed off. The last quarter of your plate should contain a high-fiber, complex carb like brown rice, whole wheat pasta, barley, quinoa, or even corn or peas. And when it comes to dessert, save the cake for a special treat and choose fresh fruit instead.