Diabetes diagnoses have been on the rise for more than a decade. In 2000 alone, more than a million adults between the ages of 18 and 79 had the disease, according to the Centers for Disease Control and Prevention. Type 2 diabetes may account for 90 percent to 95 percent of all diagnosed cases of diabetes.
Type 2 diabetes, often called adult-onset diabetes or noninsulin-dependent diabetes mellitus, is a chronic disorder of carbohydrate, fat, and protein metabolism characterized by high blood sugar levels. This increase in blood sugar levels results from defects in insulin production, insulin function, or both. Insulin is a hormone that helps control blood glucose levels. Glucose is the main form of sugar in the body. When the body cannot control its glucose levels, it has a hard time converting food into the energy the body needs to function. Unlike in type 1 diabetes, people with type 2 diabetes may produce healthy or even high levels of insulin. But be-cause their cells do not use it effectively, blood glucose levels rise. This condition is called hyperglycemia, and it is dangerous if untreated.
Symptoms, causes, & risk factors
Symptoms of type 2 diabetes usually develop slowly over time. Many people never have any symptoms. Common symptoms are usually linked to high blood glucose levels and can include excessive hunger and thirst, fatigue and weakness, frequent urination and an increase in the amount of urine passed, nausea, and visual problems.
What causes type 2 diabetes? Obesity is a major contributing factor; in fact, about 90 percent of adults and children with type 2 diabetes are obese. Type 2 diabetes is more common in people with a family history of the disease. It?s also more common among African Americans, Hispanic Americans, Pacific Islanders, Asian Americans, and Native Americans. Other risk factors for type 2 diabetes include being older than 45, having a high density lipoprotein (HDL) level equal to or less than 35 mg/dL or a triglyceride level equal to or greater than 250 mg/dL, having high blood pressure (140/90 mmHg or higher), and being sedentary. Diets skewed in favor of refined, fiber-depleted carbohydrates are thought to induce diabetes in susceptible people as well.
Link between type 2 diabetes and vitamin A deficiency
Around 95 percent of all diagnosed cases of diabetes is type 2, making it the most common form of diabetes in the United States. The condition is marked by insulin resistance, for the most part. That?s when insulin-producing beta cells in the pancreas are no longer able to function efficiently.
To find out more about the link between type 2 diabetes and vitamin A, researchers at Weill Cornell Medical College looked at the beta cells of two groups of adult mice. One group of mice was genetically modified so that they were unable to store dietary vitamin A. The other group, meanwhile, was able to store the vitamin normally from foods.
What researchers discovered was that the laboratory mice who were unable to store vitamin A also experienced beta cell death. In other words, the mice were unable to produce insulin.
Vitamin A foods to control blood sugar
What?s more, when researchers removed vitamin A from the diets of healthier mice, they noticed that this led to a great deal of beta cell loss. It resulted in far less insulin being produced and much higher blood glucose levels. Nevertheless, whenever researchers restored vitamin A to the diets of the mice, beta cell and insulin production rose steadily, and blood glucose levels returned to normal.
Interestingly, previous studies showed that during fetal development, vitamin A is vital for beta cell growth. But it was never clear whether vitamin A played the same role all throughout adulthood.
Typically, vitamin A is found in fruits, vegetables, meats and dairy products. It boosts cell growth, contributing to better vision and a healthy immune system. There are two types of the vitamin: preformed vitamin A, also known as retinol ? present in meat, poultry, fish and dairy products; and pro-vitamin A, or beta-carotene ? found in a number of fruits and vegetables.
There is some evidence to suggest too much preformed vitamin A isn?t good for you, putting you at increased risk for hip fracture, and can interfere with the beneficial actions of vitamin D in the body. So the studies emphasize vitamin A from produce, especially from healthy sources such as spinach, kale, sweet potatoes and squash. Get more of these on your plate more often!
Eat more greens to protect yourself from vitamin A deficiency
Vitamin A deficiency ??or VAD ??happens when there?s insufficient vitamin A needed for growth, development and physiological functions, not to mention those periods of stress brought on by illness. Vitamin A stimulates the production and activity of white blood cells, key to keeping your immune system running strong.
In the future, a synthetic form of vitamin A may provide added insurance. And it just might help reverse type 2 diabetes, according to Weill Cornell Medical College researchers.
But in the meantime, make those dark leafy greens a staple in your diet.