Flavonoids and the risk of type-2 diabetes

New research shows that anthocyanin consumption may be associated with a decreased risk of type-2 diabetes.

Flavonoids are found in plants and serve as pigments to help attract pollinators, filter out UV light, help in nitrogen fixation, and several other roles. An important class of flavonoids is anthocyanins. Anthocyanins are powerful antioxidants and can be found in blueberries, bilberries, raspberries, grapes, and many other plants. In addition to their antioxidant capacity, data also supports a beneficial effect of anthocyanins on insulin sensitivity. However few studies have looked at their effect on type-2 diabetes.

An article published this month in The American Journal of Clinical Nutrition looked at the relationship between flavonoids and type-2 diabetes. Researchers analyzed data from 70,359 women in the Nurses’ Health Study, 89,201 women in the NHS II, and 41,334 men in the Health Professionals Follow-Up Study. The mean age of the participants was 50, and all of the individuals examined were free of diabetes at baseline. Follow-up revealed that 12,611 cases of diabetes had developed since initial screening. Participants were asked how often, on average, they consumed different foods. Flavonoid content in each of the foods was analyzed to determine total flavonoid intake. Flavonoid intake was also broken down into five subcategories, they were: flavonols, flavones, flavanones, flavan-3-ols, and anthocyanins. The researchers found that anthocyanin consumption was associated with a decreased occurrence of type-2 diabetes. These results were observed consistently across all three study groups examined.

In addition to regular exercise and maintaining a healthy weight, a diet in flavonoid-rich fruits and vegetables may be a beneficial strategy to help lower the risk of type-2 diabetes.

Diabetes: Understanding the Disease

We are what we eat

The human body is powered by energy that is derived from the sugars we eat. During digestion, these sugars are converted by the liver into glucose. The glucose is passed into the blood stream and transported to cells throughout the body. In a healthy individual, the pancreas responds to the increased level of glucose in the blood stream following a meal by releasing a hormone called insulin. The insulin is distributed to cells in the body to activate cell receptors to accept the free glucose in the bloodstream. Once the glucose enters the cell body, it is processed through a series of reactions to generate energy (in the form of Adenosine Triphosphate, or ATP) for the cell.

The difficulty presented in diabetic patients is there is a breakdown of the system that allows for sufficient levels of glucose to reach its final intracellular destination, depriving cells of the needed ATP energy. This occurs either due to the destruction of pancreas beta cells, leading to no insulin production (type 1 diabetes), or the development of insulin resistance (type 2 diabetes). In both situations the body is left to cope with heightened blood glucose levels that degenerate into symptoms and complications.

Diabetes can present in three basic forms

The three pervasive forms of diabetes that exist in the US are gestational diabetes, type 1 diabetes and type 2 diabetes.

Pre-gestational and gestational diabetes (GDM): a somewhat common but transitory disease

Pre-gestational diabetes: Women who have an existing diabetic condition are categorized as having pre-gestational diabetes upon conception. This patient is not always aware of her diabetic condition, as it only begins presenting as a result of the pregnancy. Failure to diagnose and properly manage pre-gestational diabetes during the first trimester increases the risk of miscarriage while also placing the child at risk of developing hypoglycemia (lower than normal blood glucose levels) and birth defects in vital organs.

• Gestational diabetes (GDM): Presents in 2% -5% of all pregnancies, is temporary and treatable, and can improve or disappear after delivery. GDM develops during pregnancy, and involves a combination of inadequate insulin secretion and responsiveness, as is experienced in type 2 diabetes. The two types of GDM (A1 and A2) can be managed with as little as diet modification or require as much as insulin or other medication. Failure to properly manage a diabetic condition during pregnancy can result in health issues for the mother and child. The mother is at risk of developing hypertension, preeclampsia (hypertension and protein in the urine), and type 2 diabetes. The child faces the risk of developing hypoglycemia, jaundice, respiratory distress syndrome (RDS), childhood and adult obesity, and type 2 diabetes.

The National Institutes of Health notes that after pregnancy, 5-10% of women are found to have type 2 diabetes. Additionally, women that develop GMD have a 20-50% chance of developing type 2 diabetes within 5-10 years.

Type 1 diabetes

Formerly known as insulin-dependent diabetes mellitus (IDDM) and juvenile-onset diabetes, type 1 diabetes is the result of the body attacking and destroying the insulin producing beta cells in the pancreas. There are no known preventative measures that can minimize the onset of type 1, and the only treatment for type 1 diabetes is by delivery of insulin via multiple daily injections (MDI) or continuous subcutaneous insulin infusion (CSII, also known as insulin pumps). Though it is not clear what triggers the onset of type 1 catalyzed by a viral infection coupled with certain environmental factors (stress, chemical agents, weight, ect.) Researchers hypothesize that sufferers are genetically more susceptible to the viral infection but seem to require the environmental trigger to instigate disease presentation.

Symptoms can present at any age, and often are severe with a rapid onset. These symptoms include polyuria, polydipsia and polyphagia, weight loss, fatigue, nausea, abdominal pain, vomiting, and absence of menstruation in women. In type 1 patients, excessive eating coupled with weight loss is explained by the body deriving its energy from the breakdown of fat (a process known as ketosis), rather than from the glucose available in the food being consumed.

When the disease goes untreated, patients can suffer from severe and potential deadly complications. The high blood glucose levels experienced in type 1 diabetics can degrade the body’s vascular system, eyes, kidneys and nerves. Damage to any or all of these systems present an immediate negative impact to an individual’s overall health and quality of life. Additionally, type 1 diabetics who do not properly regulate their disease are at risk of Kussmaul breathing (deep, rapid breathing) and diabetic ketoacidosis (DKA). DKA is the result of a build-up of dangerous levels of ketones (acids) in the blood as a by-product of ketosis, and if not immediately treated it can lead to a DKA coma and potentially death.

Understanding your blood pressure for diabetes

Myth “You know if you have high blood pressure because it gives you headaches”

Truth High blood pressure does not always give you symptoms, and it is often found by chance during routine health checkups. Having your blood pressure checked at your annual diabetes reviews, and more frequently if your health professional suggest it, will be a more reliable indicator of whether your blood pressure is high.

My doctor tested me for Type 2 diabetes because I am having treatment for high blood pressure. Why is that?

Type 2 diabetes and high blood pressure are both linked to insulin resistance, so if you have one of these conditions it is common to have the other, too. If you keep both your blood pressure and your blood glucose level under control, your chances of developing long-term complications, especially heart disease, are greatly reduced.

What is high blood pressure?

If your larger blood vessels become more rigid and your smaller blood vessels start to constrict, your blood has to flow through a narrower space than before. The result is greater pressure on your blood vessel walls, which is known as high blood pressure or, medically, as hypertension. Having high blood pressure is common when you have Type 2 diabetes.

I have high blood pressure but I don’t feel sick. Why does it need to be treated?

Having high blood pressure makes you much more prone to cardiovascular disease (CVD) – a serious condition that develops over many years as your blood vessels gradually become narrower and less flexible. You may have high blood pressure without knowing it and, if it remains untreated, you may develop angina (severe chest pain) or have a heart attack or a stroke. Taking your blood pressure treatment as prescribed and having regular checkups can help prevent these serious conditions.

What should my blood pressure be?

If you have Type 2 diabetes your blood pressure should be below 130/80 millimeters of mercury (mmHg). In some situations, for example if you have already developed kidney damage (nephropathy), you may need to keep your blood pressure lower, for example, 125/75 millimeters of mercury (mmHg) to prevent further damage. Discussing your ideal blood pressure level, and ways to achieve it, with your health professional will give you the level that is right for you.

Why are there two figures in my blood pressure measurement?

The top figure refers to the level of pressure in your blood vessels as your heart contracts and pumps blood around your body. This is known as the systolic blood pressure. The second figure is the lowest pressure as your heart relaxes between beats. This is known as the diastolic blood pressure.

What can I do to lower my blood pressure?

Stop smoking and lose weight if you need to, eating more fresh fruit and vegetables and less saturated fat and salt (for example, less processed or commercially prepared meals) to help reduce your blood pressure. Physical activity will also lower your blood pressure. Take any blood pressure pills that you have been prescribed, even if they do not affect the way you feel, to help keep your blood pressure in the recommended range.

How low can my blood pressure go?

It would be unusual for your blood pressure to be under 100/60 mmHg if you are otherwise healthy. For every 10 mmHg drop in your systolic blood pressure (the first figure) toward this level, you benefit by reducing your risk of heart attack or stroke.

Food and drink for diabetes

Eating healthily is one of the main ways in which you can manage your diabetes and help keep your heart and blood vessels working efficiently. You may be overweight if you have Type 2 diabetes. If you want to lose weight, it’s good to know which foods to choose.

Types of food

What different types of food are there?
There are a number of main food types that, in combination, provide a healthy and balanced diet.

Why is it important not to eat too much salt, sugar, and fat?
Eating too much salt increases your risk of high blood pressure or makes high blood pressure worse if you already have it. Too much sugar can cause you to put on weight and make it more difficult for you to control your blood glucose level. Fat is high in calories and eating more than the recommended amount can lead to weight gain. Eating too much saturated fat also increases your risk of heart disease.

What are antioxidants?
Antioxidants are a group of healing substances found in foods. Vitamins A, C, and E, beta-carotene, and selenium – as well as many substances found in plants (phytochemicals) – have an antioxidant action. Eating foods that are rich in antioxidants has many health benefits, including protecting you from heart disease.

Can I take pill supplements such as fish oils, vitamins, and minerals?
You can, but a balanced and varied diet will provide all the nutrients you need to stay healthy. The only reason you might be advised to take nutritional supplements is if your healthcare team have diagnosed a deficiency. If you believe that you are deficient in a particular nutrient, your health professional will discuss possible actions with you.

Healthy eating for diabetes

Myth “People with diabetes can’t eat sugar”
Truth It’s impossible to avoid sugar altogether but sugar and sugar foods are converted into glucose faster than other foods so they can cause a sudden rise in your blood glucose level. Eating less sugar reduces the strain on your pancreas (the organ that produces insulin). If you want to eat sweet foods, have them at the end of meal when your body is already digesting other food in order to slow down the rise in your blood glucose.

What should I eat now that I have diabetes?
Healthy eating is the key to managing your diabetes. The principles of healthy eating for you are the same as those for everyone else. No foods are banned but eating more of some foods and less of others can help keep you healthy and your blood glucose level within the recommended range. Sometime,s you may not have a choice about what food is available but, generally, you can adapt recipes and meals so that you can enjoy food while still eating healthy.

How do I know whether I’m eating a balanced diet?
Selecting a balance of foods from the main food groups is the first step. Aim for complex carbohydrates (starches) and fiber (such as bread, pasta, and whole grains) to make up about a third of what you eat, with fruit and vegetables forming another third. Making up the rest of your food intake form protein foods and dairy products (2-3 servings daily from each group) will give you a healthy balance. Choosing lower fat alternatives where you can will help reduce your risk of heart disease.

Does it really matter what I eat? My health professional told me I’ll eventually need to take pills – and probably insulin – anyway.
Eating healthily is not simply about avoiding medication to treat your diabetes – it reduces your risk of heart and circulatory diseases, helps your digestive system work more efectivley, and helps your pancreas be more efficient if it is struggling to produce enough insulin. Type 2 diabetes is progressive and you may need pills and insulin in time, but eating healthily can help slow down this progression and make it easier to manage your blood glucose level.

Which carbohydrate-containing foods are better for me?
Starchy carbohydrates, including bread, pasta, rice, potatoes, cereals, and legumes, are better because they take longer to digest and therefore cause your blood glucose to rise more slowly than sweet carbohydrates such as white sugar, chocolate, and sugary drinks.

I know that protein doesn’t really affect my blood glucose, so does it matter what type I eat?
Protein foods that are low in fat, such as low-fat milk, low-fat yogurt and cheese, and beans, peas, and lentils will reduce your risk of heart disease. Eating oily fish two to three times a week and having less red meat will also protect your heart.

I’m a vegetarian and have Type 2 diabetes. Does this make any difference to what I should eat?
Healthy eating principles for diabetes remain the same whether you are vegetarian or following any other eating pattern. One of the advantages of vegetarian eating is that it is usually lower in fat because it doesn’t include meat. You will know what sources of protein you prefer to meat, but there is no difference in the amount or type of carbohydrate you need to eat.

My local supermarket seems to label every food as healthy – how can I tell if they are?
Many supermarkets now sell ranges of food that are healthier tan their counterparts. It could mean the food is healthier is only one aspect or several – for example, less fat, less sugar, fewer calories, or more fiber, or it could include a range of more healthy aspect. Reading the label will help you figure out which foods might help you reach your healthy eating goals. In general, processed foods will still be less healthy than those you prepare using fresh ingredients.

Do I need to eat special diabetic foods?
No foods labeled “diabetic” are often expensive and do not give you any benefits. They usually contain the sweetener sorbitol, which has 2.6 calories/gram (compared with 4 calories/gram for glucose). Sorbitol causes a slower rise in your blood glucose but in large quantities it can give you diarrhea.

Should I use artificial sweeteners?
You can use artificial sweeteners as an alternative to sugar to sweeten food and drinks, such as tea and coffee. These products contain aspartame, saccharin, cyclamate, accsulfame K, or sucralose, none of which will affect your blood glucose. Those products are classed as food additives and, for his reason, have been tested for safety.

I have high blood pressure and need to cut down on salt, how can I do this?
Reducing the amount of salt you add to your meals, either while you are cooking or at the table, will reduce your overall salt intake. Most processed and convenience foods (including stock cubes and soy sauce) tend to be high in salt, so cutting down on these can also help reduce your salt intake.

How can I make sure that when I eat fruit my blood glucose doesn’t rise too high?
The fructose in fruit and fruit juice will make your blood glucose level rise. If you eat more than one piece of fruit at a time. Eating fruit after starchy meals and spacing out your fruit intake throughout the day will give you the nutritional benefits without raising your blood glucose too high.

Which drinks will make my blood glucose level go up?
Sugar drinks such as glucose drinks, cols, lemonade, and orange juice are digested very quickly and can cause a sharp rise in your blood glucose level (which is why it is recommended that you drink them when your blood glucose is too low). Sugar added to tea or coffee will have the same effect. Because your body is unable suddenly to increase its insulin production when you have Type 2 diabetes, your blood glucose may take some time to return to an acceptable level.

Which drinks won’t affect my blood glucose level?
For day-to-day drinks, water or sugar-free drinks such as diet cola won’t affect your blood glucose level. Tea, coffee, and other hot drinks without added sugar will not affect your diabetes. Drinking them with skim or low-fat milk will ensure that their fat content is not too high. Powered drinks can have a high sugar content, so check the label to determine what effect they are likely to have.

Why are carbohydrates important in Type 2 diabetes?

Carbohydrates, also known as sugar, starch, and fiber, are broken down into glucose when they are digested, and insulin then helps that glucose move into your cells to be used for energy or stored for use later on. If you have Type 2 diabetes, your body is resistant to insulin so the glucose continues to circulate in your blood. You need carbohydrate-rich foods for energy, but choosing carbohydrate foods that your body digests at a slower rate will help reduce the demand on your insulin and thereby keep your blood glucose level more stable.

Which carbohydrates are digested quickly?

Any form of sugar, which can be called dextrose, glucose, sucrose, fructose, maltose, or lactose, is digested easily and rapidly. This is why sugar causes your blood glucose level to rise sharply, resulting in an immediate demand for insulin. Eating sugar in small quantities, and/or with or after other food, slows down its absorption so that it doesn’t have a dramatic effect on your blood glucose.

How do starch and fiber affect my blood glucose?

Starch and fiber include bread, potatoes, rice, pasta, cereals, and legumes and beans. They are broken down into glucose relatively slowly during digestion. Unlike simple carbohydrates, they do not raise your blood glucose sharply, so eating them helps keep your blood glucose level balanced.