Individuals who drink three glasses of milk a day decrease their risk of cardiovascular disease by 18 percent, according to new research published in the American Journal of Clinical Nutrition.Researchers at Wageningen University and Harvard University examined 17 studies from the United States, Europe and Japan and found no link between the consumption of regular or low fat dairy and any increased risk of heart disease, stroke or total mortality. “Milk and dairy are the most nutritious and healthy foods available and loaded with naturally occurring nutrients, such as calcium, potassium and protein, to name a few,” said Cindy Schweitzer, technical director of the Global Dairy Platform. “It's about going back to the basics; maintaining a healthy lifestyle doesn't have to be a scientific equation.”
Schweitzer said during the past three decades as research sought to understand influencers of cardiovascular disease, simplified dietary advice including consuming only low fat dairy products emerged. However, in 2010 alone, a significant amount of new research was published from all over the world, supporting the health benefits of dairy. From dispelling the myth that dairy causes heart disease, to revealing dairy's weight loss-benefits, the following is a roundup of select dairy research conducted in 2010:
- U.S. researchers examined 21 studies that included data from nearly 350,000 and concluded that dietary intakes of saturated fats are not associated with increases in the risk of either coronary heart disease or cardiovascular disease. The study was published in the American Journal of Clinical Nutrition.
- A study published in the American Journal of Epidemiology examined 23,366 Swedish men and revealed that intakes of calcium above the recommended daily levels may reduce the risk of mortality from heart disease and cancer by 25 percent.
- An Australian study published in the European Journal of Clinical Nutrition concluded that overall intake of dairy products was not associated with mortality. The 16-year prospective study of 1,529 Australian adults found that people who ate the most full-fat dairy had a 69-percent lower risk of cardiovascular death than those who ate the least.
- A Danish study published in Physiology & Behavior concluded that an inadequate calcium intake during an energy restricted weight-loss program may trigger hunger and impair compliance to the diet.
- An Israeli study published in the American Journal of Clinical Nutrition showed that a higher dairy calcium intake is related to greater diet-induced weight loss. The study sampled more than 300 overweight men and women during two years and found those with the highest dairy calcium intake lost 38-percent more weight than those with the lowest dairy calcium intake.
The amount of dairy recommended per day varies by country and is generally based on nutrition needs and food availability. “In the US and some European countries, three servings of dairy foods are recommended daily, said Dr. Schweitzer.”
The researchers also looked at bone density and structure in the lower leg in around 360 19-year-old men who had previously done sports but had now stopped training. They found that men who had stopped training more than six years ago still had larger and thicker bones in the lower leg than those who had never done sports.
“This result is particularly important, because we know that a bone with a large circumference is more durable and resistant to fractures than a narrower bone,” says Nilsson.
The researchers also studied bone density throughout the body in around 500 randomly selected 75-year-old men. Those who had done competitive sports three or more times a week at some point between the ages of 10 and 30 had higher bone density in several parts of the body than those who had not.
The researchers have therefore established that there is a positive link between exercise while young and bone density and size. The connection is even stronger if account is taken of the type of sports done.
“The bones respond best when you're young, and if you train and load them with your own bodyweight during these years, it has a stimulating effect on their development,” says Nilsson. “This may be important for bone strength much later in life too, so reducing the risk of brittle bones.”
For the first time, in a large prospective study, researchers have identified an association between high protein intake and a significantly increased risk of inflammatory bowel disease (IBD). While doctors have long suspected that diet contributes to IBD, little has been assessed, and the studies conducted have been retrospective, which are less informative because they rely on the study participants' ability to recall what they have consumed in the past. This study examined the effects of different sources and amounts of protein.
Using participants in France's E3N cohort study, researchers led by Prevost Jantchou, MD, of the Center for Research in Epidemiology and Population and colleagues identified 77 women ages 40 to 65 with validated cases of IBD. In each case, the onset of IBD occurred after the first dietary questionnaire was administered, thereby assuring that they could be studied prospectively.
Dr. Jantchou examined participants' macronutrient (protein, fat and carbohydrate) intake, and determined that more than two-thirds of them had elevated levels of protein intake. Participants were divided into three groups based on their mean protein intake: the lowest intake group had a mean daily protein intake of 1.08 grams/kg of body weight; the middle group had 1.52 grams/kg; and the highest group had 2.07 grams/kg. The FDA recommends a daily intake of 0.8 grams of protein per kilogram of body weight.
When examining the effects of specific types of protein, Jantchou found that animal protein represented a threefold risk of developing IBD in the highest group compared to the lowest group. Specifically, animal protein from meat and fish, not dairy, created an increased risk, while vegetable protein created no increased risk of developing IBD.
Researchers found that the increased risk from animal protein intake were the same for Crohn's disease and ulcerative colitis. They also found that smoking and hormonal therapy, two factors known to be related to the risk of IBD, did not change their results.
“Our findings represent a tremendous step forward in our understanding of inflammatory bowel disease,” said Dr. Jantchou. “For years we've known there was a connection between diet and IBD, and we now know specifically which aspect of diet is related to disease occurrence. The next step is to look at the effect of animal protein in patients already diagnosed with IBD to be able to give them better dietary advice.”