Fennel is low in fat and calories, cholesterol-free and high in dietary fiber. It also contains compounds that may help improve the health of diabetics. A vegetable native to the Mediterranean and parts of Asia, fresh fennel has stems, leaves and base that can be used raw or cooked in salads, soups and stir-fries. Research studying the effect of fennel on diabetes used high doses of extracted compounds and should not be duplicated at home. Do not attempt to manage diabetes with fennel until you've first spoken to your doctor.
Effect on Blood Glucose
In a study published in 2008 in the journal "Plant Sciences Research," researchers looked at the effect of giving fennel essential oil to rats. The scientists reported that a dose of 250 milligrams per kilogram of the fennel oil reduced the blood glucose level of the rats. A later study included in the June 2011 issue of the "Macedonian Journal of Medical Sciences" determined that fennel essential oil could lower the blood sugar levels of diabetes-induced rats. Research on human subjects is needed before fennel oil can be recommended as a safe and effective diabetes treatment.
Fennel is a good source of the antioxidant vitamin C, with 1 cup of the sliced vegetable containing 10.4 milligrams of the nutrient, or 11.5 percent of a man's recommended daily intake and nearly 14 percent of a woman's requirement per day. A high intake of vitamin C may lower the blood sugar and circulating lipid levels of people with Type 2 diabetes, reported an "Indian Journal of Medical Research" study in 2007. Beta carotene, another antioxidant found in fennel, is also linked to a decrease in cholesterol levels in Type 2 diabetics.
The American Diabetes Association advises diabetics to follow a diet that includes plenty of foods with a low glycemic index. These are foods that can help keep blood sugar levels stable since they do not cause rapid changes in your blood glucose. Nonstarchy vegetables such as fennel have a low glycemic index -- below 55 -- and are considered good additions to a diabetic diet, whereas foods with a medium glycemic index of 56 to 69 and high-glycemic items with a score of 70 or higher should be eaten less often.
At each meal, diabetics should aim to fill at least half of their plates with cooked or raw nonstarchy vegetables like fennel, says the ADA. Choose low-fat cooking methods such as steaming, roasting or grilling and avoid butter in favor of a small amount of mono- or polyunsaturated oils like olive, canola, sunflower or safflower oil. To help keep your sodium intake under control, use dried fennel seeds -- both ground and whole -- along with other herbs and spices instead of salt or high-sodium seasoning mixes to flavor your food.