High Glycemic Index Diet May Up Risk for Cardiovascular Disease, Death

Diets with a high glycemic index are associated with an increased risk for cardiovascular disease and death, according to a study conducted on five continents published online Feb. 24 in the New England Journal of Medicine.

David J.A. Jenkins, M.D., Ph.D., from the University of Toronto, and colleagues examined data from 137,851 participants between the ages of 35 and 70 years living on five continents to examine the association between glycemic index and cardiovascular disease. Dietary intake was determined using country-specific food-frequency questionnaires, and glycemic index and load were estimated based on consumption of seven categories of carbohydrates.

During a median follow-up of 9.5 years, there were 8,780 deaths and 8,252 major cardiovascular events. The researchers found that a diet with a high glycemic index was associated with an increased risk for a major cardiovascular event or death after performing adjustments comparing the lowest with the highest glycemic-index quintiles, both among those with and without preexisting cardiovascular disease (hazard ratios, 1.51 and 1.21, respectively). A high glycemic index was also associated with an elevated risk for death from cardiovascular causes. The results with respect to glycemic load were similar for participants with cardiovascular disease at baseline, but not for those without preexisting cardiovascular disease.

“I have been studying the impact of high glycemic diets for many decades, and this study ratifies that the consumption of high amounts of poor quality carbohydrates is an issue worldwide,” Jenkins said in a statement. “Diets high in poor quality carbohydrates are associated with reduced longevity, while diets rich in high quality carbohydrates such as fruit, vegetables, and legumes have beneficial effects.”

Source: HealthDay

To Track Carbs, Tap Into the Glycemic Index and Glycemic Load

Len Canter wrote . . . . . . . . .

Rather than just counting carbs, you might want to get familiar with the glycemic index and the glycemic load, numeric weighting systems that rank carb-based foods based on how much they raise blood sugar.

While monitoring these indicators might be especially helpful for those with diabetes, they also can be useful tools to keep others from developing diabetes and even lower the risk of heart disease, especially for women and for people who are overweight.

The glycemic index is the better known of the two. It’s a measure of the blood glucose-raising potential of carbohydrate foods compared to a reference food, like pure glucose or a slice of white bread.

The glycemic load goes one step further. It takes into account both the types of carbs in a food and the amount of carbs in a serving. The lower a food’s glycemic load, the less it affects blood sugar and insulin levels.

A food’s glycemic load gives you a more exact measurement than the glycemic index alone because even though most healthy foods are both low-glycemic index and low-glycemic load, a few higher glycemic index foods — like bananas, pineapples and watermelon — actually have low-to-moderate glycemic loads and can fit into many diets. That’s important because those three fruits in particular deliver many important nutrients.

Lowering the glycemic load of your diet happens naturally when you increase your intake of whole grains, nuts, legumes, fruits and non-starchy vegetables, and decrease foods like potatoes, white bread and sugary treats.

Using the glycemic indexes will help you refine your choices as you take steps to improve your diet.

Source: HealthDay

Charts of the Day: Glycemic Index


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What Are the Glycemic Index and the Glycemic Load?

Molly Kimball, RD, CSSD wrote . . . . . .

The glycemic index, simply put, is a measure of how quickly a food causes our blood sugar levels to rise.

The measure ranks food on a scale of 0 to 100. Foods with a high glycemic index, or GI, are quickly digested and absorbed, causing a rapid rise in blood sugar. These foods that rank high on the GI scale are often — but not always — high in processed carbohydrates and sugars. Pretzels, for example, have a glycemic index of 83; and a baked potato without the skin clocks in at 98.

Meanwhile, foods with a low GI are digested and absorbed at a slower rate, and, subsequently, cause a slower rise in blood sugar levels. These are typically rich in fiber, protein and/or fat. Examples of these include apples with a glycemic index of 28, Greek-style yogurt at 11, and peanuts at 7. Keep in mind that a low GI doesn’t mean a food is high in nutrients. You still need to choose healthy foods from all five food groups.

Diets centered on mostly low-GI foods can make it easier to achieve and maintain a healthy weight, since these foods keep us feeling fuller, longer. Low-GI diets also have been shown to improve insulin resistance, and lower glucose, cholesterol and triglyceride levels in people with type 2 diabetes.

One exception to the recommendation of a mostly low-GI diet is after intense or prolonged exercise. Consuming high glycemic foods can actually be more beneficial for muscle recovery, since they’re rapidly digested.

Glycemic Index: An Imperfect System, but Useful Tool

A food’s GI ranking only applies when a food is consumed on an empty stomach without any other type of food. As anyone who’s ever eaten food knows, this isn’t always how we eat. Sure, a bag of pretzels may be a stand-alone snack, but how often do we eat just a plain potato with nothing else?

Add a lean steak or a piece of salmon, a side of broccoli and a salad with vinaigrette, and the protein, fiber and fat all will serve to lower the glycemic index of the meal.

In addition, the glycemic index doesn’t take into account how much we’re actually consuming. The GI value of a food is determined by giving people a serving of the food that contains 50 grams of carbohydrate minus the fiber, then measuring the effect on their blood glucose levels over the next two hours.

A serving of 50 grams of carbohydrate in one sitting is reasonable for a food such as rice, which has 53 grams of carbs per cup. But for beets, a GI ranking of 64 is a little misleading. Since beets have just 13 grams of carbs per cup, we would need to consume nearly 4 cups of beets in order to cause that spike in blood sugar levels.

Glycemic Load

Glycemic load, or GL, is a formula that corrects for potentially misleading GI by combining portion size and GI into one number. The carbohydrate content of the actual serving is multiplied by the food’s GI, then that number is divided by 100. So for a cup of beets, the GL would be: 13 times 64 = 832 divided by 100 = a GL of 8.3.

As a frame of reference, a GL higher than 20 is considered high, between 11 and 19 is considered moderate, and 10 or less is considered low.

The bottom line: Even though the glycemic index isn’t a perfect system, it can be a useful tool to identify lower-glycemic foods that often are more nutrient-dense, as well as what foods are higher in refined carbohydrates.

Source: Academy of Nutrition and Dietetics

High Glycemic Index Foods and Dairy Products Linked to Acne

A study published in the Journal of the Academy of Nutrition and Dietetics has determined that there is increasing evidence of a connection between diet and acne, particularly from high glycemic load diets and dairy products, and that medical nutrition therapy (MNT) can play an important role in acne treatment.

More than 17 million Americans suffer from acne, mostly during their adolescent and young adult years. Acne influences quality of life, including social withdrawal, anxiety, and depression, making treatment essential. Since the late 1800s, research has linked diet to this common disease, identifying chocolate, sugar, and fat as particular culprits, but beginning in the 1960s, studies disassociated diet from the development of acne.

“This change occurred largely because of the results of two important research studies that are repeatedly cited in the literature and popular culture as evidence to refute the association between diet and acne,” says Jennifer Burris, MS, RD, of the Department of Nutrition, Food Studies, and Public Health, Steinhardt School of Culture, Education, and Human Development, New York University. “More recently, dermatologists and registered dietitians have revisited the diet-acne relationship and become increasingly interested in the role of medical nutritional therapy in acne treatment.”

Burris and colleagues, William Rietkerk, Department of Dermatology, New York Medical College, and Kathleen Woolf, of New York University’s Department of Nutrition, Food Studies, and Public Health, conducted a literature review to evaluate evidence for the diet-acne connection during three distinctive time periods: early history, the rise of the diet-acne myth, and recent research.

Culling information from studies between 1960 and 2012 that investigated diet and acne, investigators compiled data for a number of study characteristics, including reference, design, participants, intervention method, primary outcome, results and conclusions, covariate considerations, and limitations.

They concluded that a high glycemic index/glycemic load diet and frequent dairy consumption are the leading factors in establishing the link between diet and acne. They also note that although research results from studies conducted over the last 10 years do not demonstrate that diet causes acne, it may influence or aggravate it.

The study team recommends that dermatologists and registered dietitians work collaboratively to design and conduct quality research. “This research is necessary to fully elucidate preliminary results, determine the proposed underlying mechanisms linking diet and acne, and develop potential dietary interventions for acne treatment,” says Burris. “The medical community should not dismiss the possibility of diet therapy as an adjunct treatment for acne. At this time, the best approach is to address each acne patient individually, carefully considering the possibility of dietary counseling.”

Source: Elsevier