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Too much protein may be as dangerous as smoking

Too much protein may dramatically increase mortality
Too much protein may dramatically increase mortality
Steve Galindo

People are drawn to vegetarianism by all sorts of motives. Some of us want to live longer, healthier lives or do our part to reduce pollution. Others have made the switch because we want to preserve Earth’s natural resources or because we’ve always loved animals and are ethically opposed to eating them.

The standard American diet—high in saturated fats and processed foods and low in plant-based foods and complex carbohydrates—is making us fat and killing us slowly. According to the Centers for Disease Control and Prevention (CDC) and a division of the CDC, the National Center for Health Statistics, 64 percent of adults and 15 percent of children aged 6 to 19 are overweight and are at risk of weight-related ailments including heart disease, stroke and diabetes. A study conducted from 1986 to 1992 by Dean Ornish, MD, president and director of the Preventive Medicine Research Institute in Sausalito, California, found that overweight people who followed a low-fat, vegetarian diet lost an average of 24 pounds in the first year and kept off that weight 5 years later. They lost the weight without counting calories or carbs and without measuring portions or feeling hungry.

Thanks to an abundance of scientific research that demonstrates the health and environmental benefits of a plant-based diet, the federal government recommends that we consume most of our calories from grain products, vegetables and fruits. An estimated 70 percent of all diseases, including one-third of all cancers, are related to diet. A vegetarian diet reduces the risk for chronic degenerative diseases such as obesity, coronary artery disease, high blood pressure, diabetes and certain types of cancer including colon, breast, prostate, stomach, lung and esophageal cancer.

Now a study has found that eating too much protein could be as dangerous as smoking for middle-aged people.

Research which tracked thousands of adults for nearly 20 years found that people who eat a diet rich in animal protein are four times more likely to die of cancer than someone with a low protein diet.

The risk is nearly as high as the danger of developing cancer by smoking 20 cigarettes each day.

Previous studies have shown a link between cancer and red meat, but it is the first time research has measured the risk of death caused by regularly eating too much protein.

Nutritional advice has traditionally focused on cutting down on fat, sugar and salt. The World Health Organization will announce a consultation today suggesting that guidelines on sugar consumption should be lowered, but there have few warnings about excess protein.

The findings that were published March 4 in the journal Cell Metabolism found that people with a high protein diet were 74 per cent more likely to die of any cause within the study period than their low-protein counterparts. They were also several times more likely to die of diabetes. But this trend appeared to reverse for those aged over 65, researchers found.

High-protein food plans, such as the Atkins Diet, have become popular in recent years because of their dramatic weight-loss results.

The new research from the University of Southern California suggests that such dieters may harm themselves in the long run.

“We provide convincing evidence that a high-protein diet – particularly if the proteins are derived from animals – is nearly as bad as smoking for your health,” said Dr Valter Longo, of the university.

The researchers define a “high-protein” diet as deriving at least 20 per cent of daily calories from protein. They recommend consuming about 0.8g (0.03oz) of protein per kilogram of body weight every day in middle age. It means a person weighing 120 pounds (54.36kg) should eat about 1.6 oz. of protein a day.

Red meat as well as dairy products high in protein are also dangerous, the researchers said. A 200ml (7fl oz.) glass of milk represents 12 per cent of the recommended daily allowance of protein, while a 40g (1.4oz) slice of cheese contains 20 per cent.

Chicken, fish, legumes, vegetables, nuts and grain are healthier sources of protein. However, a chicken breast or salmon fillet still accounts for about 40 per cent of recommended daily protein intake.

“The research shows that a low-protein diet in middle age is useful for preventing cancer and overall mortality,” said Dr Eileen Crimmins, a co-author of the study.

“However, we also propose that at older ages, it may be important to avoid a low-protein diet to allow the maintenance of healthy weight and protection from frailty.”

Protein controls the growth hormone IGF-I, which helps bodies grow but has been linked to cancer susceptibility.

"The majority of Americans are eating about twice as much protein as they should, and it seems that the best change would be to lower the daily intake of all proteins but especially animal-derived proteins," at least in middle age, study senior author Dr. Valter Longo, of the University of Southern California, said in the university news release. "But don't get extreme in cutting out protein; you can go from protected to malnourished very quickly."

Overall, the findings provide "convincing evidence that a high-protein diet -- particularly if the proteins are derived from animals -- is nearly as bad as smoking for your health," Longo said in a journal news release. He was the senior author of the study conducted in humans.

If you switch from the standard American diet to a vegetarian diet, you can add about 13 healthy years to your life, says Michael F. Roizen, MD, author of The Real Age Diet: Make Yourself Younger with What You Eat. ”People who consume saturated, four-legged fat have a shorter life span and more disability at the end of their lives. Animal products clog your arteries, zap your energy and slow down your immune system. Meat eaters also experience accelerated cognitive and sexual dysfunction at a younger age.” In addition, eating meat harms the environment and passes dangerous hormones and anti-biotics through to humans.

Many vegetarians give up meat because of their concern for animals not just their health. Ten billion animals are slaughtered for human consumption each year. And, unlike the farms of yesteryear where animals roamed freely, today most animals are factory farmed: crammed into cages where they can barely move and fed a diet tainted with pesticides and antibiotics. These animals spend their entire lives in crates or stalls so small that they can’t even turn around. Farmed animals are not protected from cruelty under the law—in fact, the majority of state anticruelty laws specifically exempt farm animals from basic humane protection.

Pigs, cows, and chickens are individuals with feelings - they experience happiness, loneliness, and fear, just as dogs, cats, and people do. More than 25 billion animals are killed by the meat industry each year - in ways that would horrify any compassionate person. The average American meat-eater is responsible for the abuse and death of about 90 animals per year.

It’s almost effortless these days to find great-tasting and good-for-you vegetarian foods, whether you’re strolling the aisles of your local supermarket or walking down the street at lunchtime. If you need inspiration in the kitchen, look no further than the internet, your favorite bookseller or your local vegetarian society’s newsletter for culinary tips and great recipes. And if you’re eating out, almost any ethnic restaurant will offer vegetarian selections. In a hurry? Most fast food and fast casual restaurants now include healthful and inventive salads, sandwiches and entrees on their menus. With modern science demonstrating how unhealthy hi protein diets are to us and our environment it makes sense to try a vegetarian diet. So rather than asking yourself why go vegetarian, the real question is: Why haven’t you gone vegetarian?