Every weekday, a CNNHealth expert doctor answers a viewer question. On Friday, it's Dr. Melina Jampolis, a physician nutrition specialist.

Asked by Marci in Montana
Being a type 2 diabetic, I have too many different ideas coming at me. Do you have any advice on what diet to follow?

Expert answer

Hi, Marci,

You are definitely not alone when it comes to this issue. Approximately 25.8 million Americans suffer from type 2 diabetes (almost a third do not even know that they have the disease), and 79 million more have pre-diabetes.

With all the often conflicting diet information out there, it's challenging to figure out what to eat. While there is no single diet that works well for everyone, including those with diabetes, there are several things that can help keep your blood sugar under control and could help shrink your waistline (excess belly fat is big risk factor for diabetes).

Your overall diet pattern (this is the term most experts agree upon rather than focusing on specific macronutrient percentages) should be high in fiber and contain plenty of (whole) fruits and vegetables, moderate amounts of healthy fat, lean and plant-based protein and whole grains.

Here are several more specific suggestions:

1. Boost magnesium intake.

Magnesium is essential for proper carbohydrate metabolism, and many Americans are not getting enough. Low levels have been associated with poor blood sugar control in diabetics. The recommended daily intake is 320 mg for women and 420 mg for men.

Top food sources include fish (halibut, mackerel, flounder, sole); nuts and seeds (sunflower seeds, peanuts, almonds); dark green leafy vegetables (spinach, swiss chard); wheat germ; beans; oatmeal; baked potatoes with the skin; tofu; avocado and yogurt. Supplements are not necessary for most and should be taken only under a doctor's supervision.

2. Up your D.

Yet another reason to get plenty of vitamin D (in addition to better bone health, improved immune function and a potential decreased risk of certain types of cancer): Research suggests an association between low levels of vitamin D and an increased risk of both type 1 and type 2 diabetes.

Vitamin D appears to protect the insulin-producing beta cells of the pancreas, thereby reducing your risk of diabetes (diabetics either don't produce adequate insulin or are resistant to its effects). The latest guidelines recommend 600 IU of vitamin D until the age of 50 and 800 IU for those age 50 and above. Many experts (including myself) recommend slightly higher doses. You may want to have your blood levels checked by your doctor to determine your optimal dose.

3. Go green.

I'm not talking about recycling (although that is great too), I'm referring to eating plenty of green leafy vegetables like spinach, kale, chard, mustard greens, collard greens and romaine lettuce, to name a few.

A study in the British Medical Journal last year showed that those who ate the most greens, about 1½ servings per day, where 14% less likely to become diabetic than those who ate the least.

Green leafy vegetables are loaded with antioxidants including beta carotene and vitamin C, disease-fighting phytonutrients and vitamin K, which may also decrease your risk of diabetes. They are also high in volume and low in calories, so they can help you fill up and trim down.

4. Limit sugary drinks.

Sugar-sweetened beverages (including sodas, fruit punches, lemonades and fruit drinks) can increase your risk of diabetes by up to 25%, and the risk remains significant even if you are not overweight.