How much does diet affect your diabetes? More than you may think. In fact, strict adherence to a healthy diet can go so far as to reverse type 2 diabetes in some patients.
That’s what researchers discovered in a study published in 2017. They found that nearly half of the people who went on a six-month diet plan and lost an average of 30 pounds went into remission and no longer had diabetes.
That doesn’t mean everyone can cure diabetes through diet alone, but it does suggest that diet can play a huge role in how you manage your diabetes and the quality of life you may enjoy.
Why Does Diet Matter in Managing Diabetes?
Diet affects diabetes in two primary ways:
- Encourages weight loss
- Helps control blood sugar levels
The more you can affect these two factors, the more control you’ll have over your diabetes and your life.
Encourages Weight Loss
Diabetes is a disease in which the body is no longer able to keep blood sugar levels in a healthy range. Most of the foods you eat are changed into “glucose” in the body, which is the body’s preferred form of fuel. It’s like your body’s gasoline. Then, hormones like insulin work to get that glucose into the cells where it’s needed for energy. Whatever isn’t needed, the body stores away as fat.
If your hormones don’t work as they should, that glucose stays in your bloodstream where instead of doing the body well, it causes harm. It’s like you’ve got plenty of gas in the tank, but you can’t get it into the engine where it’s needed, so it just remains in the tank, building up to dangerous levels.
When the body has excess weight, the cells become less sensitive to insulin. They shut down their insulin receptors, in effect, saying, “Enough is enough! We’re full!” The insulin tries, but can’t get the glucose into the cells, so it remains in the bloodstream. This is called “insulin resistance,” and is one of the main causes of type 2 diabetes.
Helps Control Blood Sugar Levels
There are two main types of foods that spike or raise blood-sugar levels:
Carbohydrates have the greatest effect on blood sugar levels, although they’re not all the same. To explain just how each type directly affects blood sugar, scientists and doctors developed the “glycemic index,” which ranks carbohydrates on a scale from 0 to 100. Those high on the scale break down quickly in the digestive system, spiking blood levels and causing significant fluctuations in blood sugar. Those lower on the scale are digested more slowly, creating more stable blood sugar levels.
This is why diabetics are encouraged to follow the glycemic index when planning out meals. Low-glycemic foods have a rating of 55 or less, while those in the 70 to 100 range are considered high-glycemic foods. Eating too many in the high range can result in blood sugar spikes. Eating more in the low range can help not only control blood sugar levels but improve weight loss too.
Fatty foods can be dangerous for diabetics too but, again, it depends on what kind of fat we’re talking about. In a 2016 review, researchers examined more than 100 different studies in which more than 4,200 participants followed different diets. Results showed that some fats raised blood sugar levels more than others.
In general, there are two basic categories of fats:
- Saturated fats: These are considered unhealthy as they can collect in the arteries and lead to cardiovascular disease. Examples include butter, cream, fatty cuts of meat, palm oil, coconut oil, deep-fried foods, and baked goods.
- Unsaturated fats: These can have a positive effect on health.
Inside the unsaturated category are two subcategories that differ mainly in chemical makeup:
- Monounsaturated fats are considered to be “healthy” fats. Examples include olive oil, sesame seed oil, peanut butter, certain nuts, and avocados.
- Polyunsaturated fats are also healthy fats. Examples include sunflower seeds, pumpkin seeds, safflower oil, corn oil, and pine nuts. The popular and healthy omega-3 fats are also polyunsaturated fats. Examples include fatty fish, flaxseeds, chia seeds, and walnuts.
For this study, scientists divided the fats consumed into three categories: saturated, monounsaturated and polyunsaturated and also measured carbohydrate intake. They found that following a diet rich in monounsaturated or polyunsaturated fat instead of meals rich in carbohydrates and saturated fat improved blood sugar control. The most consistent benefits occurred in those increasing consumption of polyunsaturated fats in place of either saturated fats or carbohydrates.
Because unhealthy fatty foods are typically calorie-dense — high in calories — eating too many of them can also lead to overweight and obesity that, again, reduces blood sugar control. Therefore, we can see that diet can have a large effect on diabetes. The question then becomes: what should we eat and what should we avoid?
15 Foods to Enjoy Regularly If You Have Diabetes
Considering the information above, the main goals are to lose weight and keep blood sugar levels under control. The following foods can help you do that.
Cinnamon is not only a powerful antioxidant, but it has also been shown in several studies to help lower blood sugar levels and improve insulin sensitivity.
Spinach, kale, arugula, collard greens and Swiss chard — these and other leafy greens are extremely nutritious and low in calories and carbohydrates, plus they’re a great source of healthy antioxidants. You can eat these most any time and rest assured that they won’t affect your diabetes negatively.
These are rich in those healthy polyunsaturated fats, which can help prevent cardiovascular disease. Because diabetics are at an increased risk for this disease, these are good foods to eat regularly. Try salmon, anchovies, herring, sardines, and mackerel.
Berries are super high in antioxidants and are packed with vitamin C and other important nutrients. They have been shown in studies to help reduce insulin levels after a meal. They’re also rich in fiber and will help keep you satisfied.
It used to be that we worried about eggs because they’re high in cholesterol. Scientists thought that cholesterol would increase the risk of heart disease, but more recent studies have shown that the cholesterol in eggs does not affect cholesterol buildup in arteries. Eggs are rich in protein, so they can keep you full, helping in weight-loss efforts. Studies have also found that they can improve insulin sensitivity and increase levels of HDL “good” cholesterol.
Yogurt contains healthy probiotics, which have been linked to improved blood sugar control and a reduced risk of heart disease. Greek yogurt is higher in protein than regular yogurt, so it will keep you satisfied longer and will break down more slowly in the body, avoiding blood sugar spikes. It also contains fewer carbohydrates than regular yogurt.
All types of nuts contain fiber, which helps slow digestion and stabilizes blood sugar levels. Most are also low in carbohydrates. Some research has suggested that they may help lower blood sugar and assist in weight loss. Choose Brazil nuts, almonds, hazelnuts, pecans, macadamia nuts, and walnuts.
This is a super nutritious vegetable that’s low in carbohydrates and rich in nutrients like vitamin C. It may also help lower insulin levels. In a 2012 study, those who received supplements of broccoli sprouts powder experienced a significant decrease in insulin resistance.
Extra-virgin Olive Oil
This contains healthy monounsaturated fats that can help keep you satisfied after a meal and has also been linked with a reduced risk of cardiovascular disease.
As long as you choose the varieties packed in water, you’ll get a low-fat, low-calorie, protein-rich food that works great for sandwiches. Tuna is also a good source for those healthy omega-3 fatty acids.
Skinless Turkey & Chicken
These are lean-meat choices that serve well as the main course in your meals while supplying filling protein. They’re low in fat as long as you prepare them in a healthy way.
Flaxseeds & Chia Seeds
These foods are naturally high in fiber, which means they’ll help keep you satisfied and can reduce the urge to snack between meals. They are also very low in carbohydrates, so they won’t raise blood sugar levels. In some studies, they have been shown to help lower insulin sensitivity.
If you’re craving something sweet, dark chocolate is your smartest choice. It’s high in antioxidants and has been linked with a reduced risk of heart disease. Make sure you look for varieties that have at least 70 percent cocoa and that you limit your consumption to small pieces. Too much can raise your blood sugar levels.
This food contains high amounts of magnesium, which can help the body use glucose more efficiently. It’s also filled with fiber and other nutrients that are good for you. Steel-cut oats are the best option over quick-cooking types.
15 Foods to Avoid If You Have Diabetes
These are the worst — way too much sugar. Add to this category sweetened tea and lemonade. They’re loaded with fructose, which increases blood sugar levels and has been linked to insulin resistance. Choose water, low-fat milk, and unsweetened tea and coffee.
These are typically high in carbohydrates and fat, which makes them bad snack choices. Choose nuts or cut-up vegetables instead.
Convenient and tasty, maybe, but these ready-made foods are also typically high in carbohydrates, fat, and calories. If you can’t curb your pizza craving, look for a veggie pizza or make your own with fresh herbs and veggies. Thin crusts are also better than thick or pan varieties. If you’re buying pizza in a restaurant, choose the thin crust and lean meats like chicken. Say “no” to the extra cheese and limit your portions. Eat a salad first.
Hot Dogs & Bacon
These are processed meats that are linked to weight gain and heart disease. Recent studies have also indicated they can increase the risk of diabetes for those that don’t have it yet. If you’re at a sports event and just can’t resist, choose a whole-grain bun if possible or eat it with only half the bun to cut carbohydrates.
White Bread & White Pasta
These are high in carbohydrates and break down too quickly in the digestive system, raising blood sugar.
Sugary Breakfast Cereals
These are way too high in sugar and way low in nutrition. Choose oatmeal and eggs instead or look for whole-grain options that are high in fiber and low in sugar.
Donuts, Cinnamon Rolls & Pastries
These are high in saturated fats, calories, and carbohydrates. Look for diabetes-friendly recipes for alternative types of desserts.
These are made from white potatoes, which are high in carbohydrates, then they’re typically fried in unhealthy oils.
Although fruit is generally healthy food, dried fruit results in higher concentrations of sugar, which is not what you want. Dried fruit is also high in carbohydrates.
Whole fruit delivers fiber along with natural sugars, helping reduce the risk of raising blood sugar levels. Fruit juices are stripped of fiber and are high in sugar. Eat the whole fruit instead. You can also put some whole fruit into a pitcher of ice water for extra flavor.
Although coconut oil can have some health benefits, it still contains saturated fat, which can increase the risk of heart disease and weight gain. Substitute coconut oil for olive or safflower oil.
If you love Starbucks, it’s time to make a change. Most flavored coffee drinks are packed with sugar and carbohydrates. Choose plain coffee or espresso with half and half.
Most of the selections are high in carbohydrates and fat — not a good idea. Portion sizes are often super large too, which can encourage overeating. If your friends are set on Chinese, ask the server to pack up two-thirds of the serving in a to-go box, then choose items that aren’t fried.
Fried Chicken, Hamburgers & Fatty Meats
These are high in fat, and regular consumption can increase the risk of being overweight and developing cardiovascular disease. Look for lean alternatives, like chicken, turkey, and fish. When you’re craving a burger, make one at home with lean meat and mustard. However, limit the mayonnaise.
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