NDSU meat scientist says beef can be part of healthy diet
FARGO — North Dakota State University researcher Eric Berg says beef’s reputation as being unhealthy is likely undeserved.
Using pigs, because they’re omnivores like humans and their bodies react to food in similar ways, he recently found that even when pigs ate more calories on a diet of ground beef with 35 percent fat than pigs eating a diet of corn, soybean meal and corn oil (a diet he says is equivalent to a person’s recommended daily allowance), the pigs eating beef gained less body fat over the 84-day research period.
Berg said calories do count. The pigs on the beef diet still got fat. But, he said, not every calorie is equal, and it’s not animal fat and protein that has led to the obesity epidemic in our country. Instead, he blames people eating too much sugar and too many carbs, which our bodies turn into sugar.
“Calories from different food sources matter and the effect that they have on physiology is more important than total caloric count,” he said. “This whole paradigm shift of low fat in the ’80s, when that really kicked into gear, that’s when we see the obesity rates going up. That’s really when you see a rapid increase of adult-onset diabetes and creeping down into kids.”
When fat was cut out of foods, sugar was added, Berg said.
“So this is what we’re looking at, the difference between the types of food that we eat, how they affect the release of hormones, how they affect your metabolism and physiology,” he said.
When people eat more sugar than they’re burning, Berg said, the body stores those sugars as fat.
“Sugar is really the bad thing now,” Berg said. “It’s just nobody’s gotten on the bandwagon over meat.”
Meat is nutrient-dense, does not affect blood sugar, is a complete source of essential amino acids and fatty acids, and has bioavailable iron, he said.
“We’re going to rely on science to show that the negative press that red meat gets is probably unfounded,” Berg said.
The North Dakota Beef Commission funded much of Berg’s research.
“For decades, the beef industry has defended its product, and we’ve tried to do that with really solid research and yet we still have taken a bad rap with the press and with some in the nutrition world,” said Nancy Jo Bateman, North Dakota Beef Commission executive director. “It’s research like this that I think brings the science to the party. It helps us to have credible research that can be validated and can tell people that lean beef can be incorporated as a part of any healthful diet.”
The industry has 29 lean cuts of beef, and Bateman said that number will soon be well into the 30s.
“The other thing that’s really important for people to understand is in that 3-ounce cooked portion, you’ve got a full house of nutrients,” Bateman said.
Eaten in moderation with a variety of other foods, Bateman said beef can still be a significant, healthful part of any diet.
“You can eat beef without the guilt,” she said.
Kim Vonnahme, an associate professor in NDSU’s Department of Animal Sciences, who worked with Berg on some of his research, started eating a low-carb, high-fat diet in May and said she is more energetic, more flexible, and has lost 49 pounds.
“It’s kind of like I’m cheating because I’m not hungry,” she said of the diet from www.dietdoctor.com, adding that she doesn’t exercise much.
She eats foods such as cheese, salami, cream, eggs, nuts and bacon, and said she doesn’t count calories or feels hungry. She also eats berries and any vegetables that grow above the ground.
Dieting was always a struggle before. Now, Vonnahme said she loses weight without thinking about it.
“When you eat fat, the body releases a hormone that tells your brain that you’re satisfied,” she said. “Doing this and seeing Eric’s data, it makes sense. All these pieces are there and they seem to fit together.”
Vonnahme said the research she did into the diet showed that people’s cholesterol either lowered or did not change. She had her blood checked before she started the diet and said she plans to have it tested again soon to make sure it’s not increasing.
“It’s kind of exciting to talk about, but it’s one of those things where people don’t believe me,” she said.
Too much bad cholesterol (LDL) combines with white blood cells and forms plaque in the veins and arteries, which leads to heart disease and stroke, according to the American Heart Association. The AHA says a desirable cholesterol level is less than 200 mg/dL.
Berg said the total cholesterol, good cholesterol and bad cholesterol did go up for the pigs on the red meat diet, but it was still less than 120.
The grain-fed pigs’ cholesterol went up too, but Berg said it was significantly lower. Insulin also increased in the grain-fed pigs, but stayed flat in the pigs eating beef.
One thing Berg didn’t expect was how much beef the pigs ate. They were allowed to eat as much as they wanted and some ate 21 pounds a day.
“I thought, it’s 35 percent fat, they’re going to meet their energy requirements and they’ll quit eating it,” he said. “They didn’t quit eating it.”
When he asked an internationally renowned swine nutritionist why his pigs ate so much, he said he was told “they obviously liked it.”
“Now I’ve got to figure out physiologically why they would just keep eating,” he said.
Studying pigs instead of humans allowed Berg to take muscle, fat and liver biopsies. He is also able to control parentage, climate and other environmental factors. Studies with people are also often based on what the subjects remember eating, Berg said. With his study, he knows exactly what the pigs ate.
Berg has submitted four abstracts of his research for presentation at the Midwest section of the American Society of Animal Science meeting in March. He also plans to present his data at the national meeting of the American Meat Science Association in June.