What is the best prediabetes and diabetes diet?
What to eat has always been challenging as we are living in a plethora of food abundance, making food choices each day. The foods below are recommended and advised to consume to prevent/control prediabetes/diabetes.
1. Whole Grain
The first component of prediabetes and diabetes diet is whole grain. Whole grains consumption is known to reduce the risk of diabetes and cardiovascular mortality. A study has shown that 1 serving per day (28 g) of whole grains reduces the risk of cardiovascular disease by 14% and cancer mortality by 3%. 
Beta-glucan, a soluble fiber found in oats and barley, is proven to have antidiabetic and cholesterol-lowering effects. The stickiness of oats and barley from the soluble fiber creates viscosity, which slows down the absorption and diffusion of glucose, reducing postprandial hyperglycemia and insulin secretion.
Brown rice includes the outermost layer of the rice kernel which helps keep the nutritional values including dietary fiber, essential fatty acids, and various vitamins and trace elements. According to a recent study, not only brown rice consumption group maintain lower blood sugar, but it also helps to stay fuller longer than the white rice consumption group. 
Quinoa, a small, nutrient-packed ancient grain, is widely available and can be easily found. It is known to be a complete protein, with all nine essential amino acids. The antioxidant and anti-inflammatory properties of quinoa have been proven to lower the oxidative stress that could lead to diabetes and cardiovascular diseases.
2. Lean Meats
The second important food for a diabetes diet is lean meat. Studies have shown that unprocessed, lean part of meat (<4 servings per week) is not harmful to diabetes or cardiovascular disease risk. 
Examples of lean meats include:
chicken or turkey (white meat, dark meat, without skin)
fresh cod and tuna fish
beef trimmed in fat (e.g. round, sirloin, flank, tenderloin, roast)
Lean meat is a great source of
Iron – carries oxygen from the lungs to all parts of the body, and also stores oxygen in muscle tissues.
Zinc – major player in the immune system and wound healing, building proteins.
B vitamins – vitamin B12 can be naturally found in animal protein, and helps form red blood cells, and DNA, along with brain and nerve development.
3. Healthy Fats
The third component of a diabetes diet is healthy fats.
The Mediterranean diet, which is rich in monounsaturated fat and polyunsaturated fat, including olive oil, avocados, nuts, seeds, and fish is proven to improve glycemic control, insulin resistance along with reducing cardiovascular vascular risks.
Currently, consuming nuts regularly (daily or at least 3 times per week) of a handful of raw, unsalted nuts (about 30g, 3 tablespoons, 160kcal) is recommended.
4. Legumes, plant-based protein
Plant-based proteins such as lentils, beans, peas, tofu, and tempeh, are associated with lowering the risk of developing diabetes.
A serving of legumes is ½ cup, a handful. They are rich in protein and fiber and several micronutrients. They also contain natural enzyme inhibitors that help slow down the carbohydrates and lipids in the small intestines, contributing them to being slowly digested and absorbed, and causing a slower and smaller rise in blood sugar levels.
Studies have found that
protein may be responsible for blood glucose regulations
chickpeas, hummus, and chickpea flour reduces blood glucose response
when pulses are added to pasta, it significantly lowers glucose level compared to regular pasta without the pulses. 
5. Fruits and vegetables
Fruits and vegetables are great sources of flavonoids, antioxidants compounds (vitamin C, E, carotenoids), potassium, and folate, as well as full of dietary fiber that helps to delay the absorption of carbohydrates and secrete insulin adequately and promote to keep fullness longer.
According to 2016 Meta-analysis study, 1) Increased consumption of fruit, especially berries (strawberries, blueberries) 2) Increased consumption of green leafy vegetables, yellow vegetables, or cruciferous vegetables, could reduce diabetes risks. 
Green leafy vegetables: spinach, collard greens, romaine, mustard greens, lettuce, kale, etc.
Yellow vegetables: carrots, yellow peppers, pumpkin, sweet potatoes, winter squash, golden beets
Cruciferous vegetables: broccoli, cauliflower, bok choy, brussel sprouts, cabbage
Yogurt is made by adding the “good” bacteria to milk and then kept at a specific temperature. During fermentation, the “good” bacteria thicken the milk and give the tangy taste.
It is rich in calcium, magnesium, phosphorus, vitamin D, and high-quality proteins support the immune system, and benefit digestion and bowel movement.
Probiotic bacteria components and some fatty acids components may have been contributing factors to preventing diabetes risk by reducing insulin resistance risk. 
7. Coffee and tea
The last component of diabetes diets is coffee and tea. Coffee consumption or tea (black, green tea), without sugar or cream/milk, inversely associated with diabetes risk.
Caffeine, phenolics (e.g. chlorogenic acid [CGA]), lignans, trigonelline, N-methylpyridinium, minerals and vitamins, proteins, and lipids in coffee have been found to play important role in insulin regulation. 
Phytochemicals such as catechins, gallic acid, caffeic acid, kaempferol, myricetin, and quercetin in green tea have been shown to aid weight loss, reduce blood glucose level in prediabetes and diabetes patients. 
In summary, consuming whole grain, lean meats, healthy fats, fruits and vegetables, yogurt, and coffee and tea (without sugar or milk/cream) have been demonstrated to have a preventive effect on preventing diabetes risk. Finding, choosing, and preparing these foods based on your time and availability, can be challenging.
Personalized and individualized diabetes diets, based on your goals and comfort level, are the best way to reduce your blood glucose level.
If you want to know more about personalized prediabetes & diabetes diet, your personalized dietitians at DoctorHere are here for you.
5 Essential Tips On How To Reverse Prediabetes. https://www.doctorhere.com/how-to-reverse-prediabetes/
8 Reasons Why Your Blood Sugar Rises or Falls. https://www.doctorhere.com/blood-sugar-rise-and-falls/
How Do Doctors Check for Type 2 Diabetes. https://www.doctorhere.com/type-2-diabetes-diagnosis/
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