The first advice that people with diabetes get from their friends and relatives is to cut down or even stop eating starchy things like rice, bread and potatoes. This advice is of course par for the course in a general way but is a somewhat extreme step that a diabetic need not resort to at the drop of the hat.
It is a common misconception that people with diabetes need to avoid all potatoes and other starchy foods. The reason for this misconception is that starchy foods are high in carbohydrates and tend to have a high glycemic index (GI). GI is a useful system for ranking foods from 0 to 100 according to their potential to raise blood sugar levels. Foods with a high GI raise blood sugar more than those with a low GI.
According to the American Diabetes Association (ADA):
low GI foods have a GI of 55 or less
medium GI foods have a GI of 56 to 69
high GI foods have a GI of 70 or more
While some varieties of potato do have a high GI, other factors can balance this out, including the portion size and method of preparation. The ADA recommends combining a high GI food with low GI foods to help balance a meal. They the portion size is key to enjoying starchy foods as part of a healthful meal plan.
Another consideration is the cooking method. Deep or shallow frying potatoes in certain oils and fats, such as animal fats, can make them high in saturated and trans fats, which can increase the risk of heart disease. The best way to prepare potatoes is to boil or steam them. Both boiled and steamed potatoes are rich in vitamins, minerals, and fiber but very low in fat, sugar, and salt.
It is best to eat potatoes as part of a balanced, healthful meal. Other meal components, such as low GI foods, fiber, lean protein, and healthful fats, can help balance a meal out.
Eating high-fiber foods is beneficial as these help control blood sugar levels and increase the feeling of fullness. Low GI foods can include other non-starchy vegetables.
Sweet potatoes are one of the best types of potato for people with diabetes as they are low GI and contain more fiber than white potatoes. Sweet potatoes are also a good source of calcium and vitamin A.
Boiling is a healthful method of cooking potatoes. The preparation and cooking methods that a person uses can affect both the GI and the nutritional content of potatoes. For instance, whole potatoes have a lower GI than mashed or diced potatoes. Allowing potatoes to cool slightly before eating them can also be beneficial. Cooking a potato makes the starch more digestible, which raises the GI. After cooling, the potato becomes less digestible again, which may lower the GI.
The most healthful way to cook potatoes is to boil, steam, or microwave them without adding any other ingredients. Preparing potatoes in this way will ensure that they are very low in sugar, salt, and fat. Keeping the skins of the potatoes on can provide additional fiber. Also, up to 50% of the phenolic compounds in potatoes are present in the skin and attached flesh. Phenolic compounds have antioxidant properties that may be beneficial to health.
Some potato dishes are more suitable than others for people with diabetes. For example, a potato salad can be a good option as the potatoes are whole. However, other ingredients, such as mayonnaise, should be low-fat with no added sugar. People can try this potato salad recipe which uses low-fat mayonnaise and light sour cream to reduce the fat content.
Any recipes that use mashed or crushed potato, such as potato pasta, are less appropriate for people with diabetes. Processing the potato in this way increases its GI and the potential impact that it has on a person's blood sugar levels. It is also best to avoid fried potatoes as frying them increases their calorie and fat content. So the next time you greet your diabetic friend at the dining table, don’t ask him to stop eating potatoes. Let him do it judiciously and still enjoy the meal thoroughly.
(MNT 25 October 2018)