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The Physicians Committee

Don’t Be a Processed-Meat-Risk Denier

September 7, 2017   Dr. Neal Barnard   processed meat


Don't be a processed meat denier

The new documentary What the Health is fueling an important conversation about the health risks of hot dogs, bacon, and other processed meats. Here at the Physicians Committee, we’ve been urging people to “drop the hot dog” and “ban the bacon” for years. Now, a new report—that analyzed 99 studies including data on 29 million people—adds even more evidence showing that it’s unwise to deny the dangers of processed meat.

The authors of “Diet, Nutrition, Physical Activity and Colorectal Cancer,” the new report by the American Institute for Cancer Research and the World Cancer Research Fund, concluded that “consumption of processed meat is a convincing cause of colorectal cancer.” The report also found that eating high amounts of red meat and being overweight or obese can increase colorectal cancer risk.

There is good news. The report concluded that eating approximately three servings of whole grains, such as brown rice or whole-wheat bread, daily reduces the risk of colorectal cancer by 17 percent.

Visit DropTheHotDog.org to learn more about the dangers of processed meats.

no amount of processed meat is safe

NBA Star Damian Lillard Goes Vegan

September 7, 2017   Dr. Neal Barnard   vegan


NBA all star Damian Lillard goes vegan

How does an NBA All-Star prep for the upcoming season? A vegan diet, of course. Damian Lillard, who plays basketball for the Portland Trail Blazers, is trying to get down to 190 pounds (his rookie weight, according to NBA.com) to get ready for the upcoming season that begins on Oct. 17. No problem on a healthy vegan diet—which can lead to twice as much weight-loss as other diets! The same plant-based foods will also provide him with all the protein and nutrients that keep vegan bodybuilders strong.

Yesterday on Instagram, he shared a video of some of the foods he’s using to fuel up, while losing weight.



Checking in at 190 lol... strong and fast babyyyyy

A post shared by Damian Lillard (@damianlillard) on


Lillard joins a growing number of professional athletes who know that plant-based diets improve performance, including fellow NBA player Jahlil Okafor, the NFL’s Trent Williams, David Johnson, and Griff Whalen, tennis stars Venus Williams and Novak Djokovic, and dancer Derek Hough.

And just this week, longtime vegan and my good friend Rich Roll competed in the Ötillö Swimrun World Championship, an adventure race in which athletes swim and run 46 miles across 26 islands of the Stockholm Archipelago.

Want to improve your athletic performance with a vegan diet? Check out Food Power for Athletes fact sheet.

Does Sugar Cause Diabetes?

August 7, 2017   Dr. Neal Barnard   diabetes, type 2 diabetes


Does Sugar Cause Diabetes?

The recent film What the Health raised the question as to whether sugar or other carbohydrates cause diabetes. 

The notion is understandable. Blood sugar levels are high in diabetes, so a common idea has held that eating sugar somehow triggers the disease process. However, the major diabetes organizations take a different view. The American Diabetes Association1 and Diabetes UK2 have labelled this notion a “myth,” as has the Joslin Diabetes Center,3 which wrote, “Diabetes is not caused by eating too much sugar.” These and other organizations have worked to educate people about the causes of diabetes and the role that foods play in the disease process.

Type 1 diabetes is an autoimmune disease. Type 2 diabetes—the most common form of the disease—is caused by insulin resistance and pancreatic failure. Here is what you need to know: 

Sugar Is the Body’s Fuel 

The human body runs on glucose, a simple sugar. Just as gasoline powers your car, glucose powers your muscles, your brain, and the rest of your body. Glucose comes from fruit and from starchy foods, such as grains, beans, and potatoes, and your body can also produce it when needed. Without it you would die.  

Diabetes means having higher-than-normal blood glucose values. It comes in three common forms:  

  • Type 1 diabetes is caused by the destruction of the insulin-producing cells of the pancreas, usually through an autoimmune process. The triggers for this process are under investigation and may include dairy proteins, viruses, or other factors.
  • Type 2 diabetes typically starts with insulin resistance. That is, the cells of the body resist insulin’s efforts to escort glucose into the cells. What causes insulin resistance? It appears to be caused by an accumulation of microscopic fat particles within muscle and liver cells.4 This fat comes mainly from the diet—chicken fat, beef fat, cheese fat, fish fat, and even vegetable fat. To try to overcome insulin resistance, the pancreas produces extra insulin. When the pancreas can no longer keep up, blood sugar rises. The combination of insulin resistance and pancreatic cell failure leads to type 2 diabetes.
  • Gestational diabetes is similar to type 2 and occurs during pregnancy. 

What Fuels the Diabetes Epidemic? 

In Japan, China, and other Asian countries, the transition from traditional carbohydrate-rich (e.g., rice-based) diets to lower-carbohydrate Westernized eating habits emphasizing meats, dairy products, and fried foods has been accompanied by a major increase in diabetes prevalence. Similarly, in the United States, a meat-based (omnivorous) diet is associated with a high prevalence of diabetes, compared with dietary patterns emphasizing plant-derived foods. In the Adventist Health Study-2, after adjusting for differences in body weight, physical activity, and other factors, an omnivorous diet was associated with roughly double the risk of diabetes, compared with a diet omitting animal products.5

Type 2 Diabetes Prevalence
Odds Ratio of Type 2 Diabetes


In clinical trials, when people change from an omnivorous diet to a low-fat vegan diet, diabetes typically improves significantly.6 

These findings from observational studies and clinical trials resonate with the finding from magnetic resonance spectroscopy showing that fat inside the cells leads to insulin resistance, the first step toward type 2 diabetes. 

Sugar Is Falling, Diabetes Is Rising

It has become fashionable in recent years to blame sugar for many health problems. However, per capita sugar consumption has actually been falling in the United States since 1999, when bottled water and sugar-free beverages began to edge sodas off the shelf. At the same time, consumption of cheese and oily foods has steadily increased, as has diabetes prevalence. This suggests that something other than sugar is driving the diabetes epidemic. 

A number of studies have looked for relationships between sugar and diabetes risk. A 2017 meta-analysis, based on nine reports of 15 cohort studies including 251,261 participants, found no significant effect of total sugars on the risk of developing type 2 diabetes.7 Those consuming the most sugar actually had a 9 percent lower risk of developing diabetes, compared with those consuming the least sugar, although the difference was not statistically significant (meaning that it could have been a chance result). Similarly, fructose was not significantly associated with diabetes risk. Sucrose appeared to have a significant protective association. Those consuming the most sucrose had 11 percent less risk of developing type 2 diabetes, compared with those consuming the least.

Other studies have focused, not on sugar overall but specifically on sodas and other sugar-sweetened beverages. Many have found no significant relationship, apart from sugar’s extra calories that lead to weight gain. For example, the Women’s Health Study,8 the Atherosclerosis Risk in Communities Study,9 the Black Women’s Health Study,10 and the Multi-Ethnic Study of Atherosclerosis found no significant associations between sugar consumption and diabetes risk after adjustment for measures of body weight. Some studies have had mixed results, exonerating sucrose, but indicting glucose and fructose.12,13 And some studies have shown associations between sugar-sweetened beverages and diabetes that persist after adjustment for body weight.14,15

A 2015 meta-analysis summarizing the results of 17 cohorts concluded that, after adjustment for body weight, a daily 250 mL serving of sugar-sweetened beverages was associated with approximately 13 percent higher risk of developing diabetes.

If sugars in general are not associated with increased diabetes risk, but sodas are, it suggests the possibility that something other than sugar explains this relationship.16 Sodas are often accompanied by cheeseburgers, chicken nuggets, and other unhealthful foods. That is, soda consumption can be a sign of a diet focusing on fast foods or an overall unhealthful diet and lifestyle. And sugary snack foods (e.g., cookies and snack pastries) are often high in fat; the sugar lures us in to the fat calories hiding inside. Some, but not all, observational trials have sought to control for these confounding variables. 

Still, Sugar Is Not a Health Food 

So our bodies actually run on sugar—that is, glucose. Moreover, sugar has only 4 calories per gram (much less than fats and oils, which have 9 calories per gram), and sugar’s calories can be used for metabolic needs or stored as glycogen. So does that mean that added sugars are innocuous? 

Certainly not. Although glucose is an important fuel for the body, there is no physiological need for added sugars. Because sugar dissolves into sodas and snack foods, it is easy to consume surprisingly large quantities of it, potentially contributing to weight gain. In turn, higher body weight can make type 2 diabetes more likely to occur. 


Diabetes is a serious disease. Its most common form, type 2 diabetes, has become a worldwide epidemic as Western eating habits spread. An understanding of its causes is essential to identifying means of combatting it.

The roots of type 2 diabetes remain in insulin resistance and pancreatic failure, and the blame for the current diabetes epidemic lies in an overall dietary pattern emphasizing meat, dairy products, and fatty foods, aided and abetted by sugary foods and beverages, rather than simply in sugar alone. A diet emphasizing vegetables, fruits, whole grains, and legumes and avoiding animal products helps prevent diabetes and improves its management when it has been diagnosed. 

The idea that “eating sugar causes diabetes” is inaccurate. Nonetheless, avoiding added sugars is a helpful step, and it should be taken in addition to a healthful plant-based eating pattern, not instead of it.  


  1. American Diabetes Association. Diabetes Myths. http://www.diabetes.org/diabetes-basics/myths/. Accessed August 6, 2017. 

  2. Diabetes UK. Myth: Sugar Causes Diabetes. https://www.diabetes.org.uk/Guide-to-diabetes/Enjoy-food/Eating-with-dia.... Accessed August 6, 2017.
  3. Joslin Diabetes Center. Four Myths about Diabetes. http://www.joslin.org/info/4_Myths_About_Diabetes.html. Accessed August 6, 2017.

  4. Petersen KF, Dufour S, Befroy D, Garcia R, Shulman GI. Impaired mitochondrial activity in the insulin-resistant offspring of patients with type 2 diabetes. N Engl J Med. 2004;350:664–671.
  5. Tonstad S, Butler T, Yan R, Fraser GE. Type of vegetarian diet, body weight and prevalence of type 2 diabetes. Diabetes Care. 2009;32:791-796.
  6. Yokoyama Y, Barnard ND, Levin SM, Watanabe M. Vegetarian diets and glycemic control in diabetes: a systematic review and meta-analysis. Cardiovasc Diagn Ther. 2014;4:373-382.
  7. Tsilas CS, de Souza RJ, Blanco Mejia S, et al. Relation of total sugars, fructose and sucrose with incident type 2 diabetes: a systematic review and meta-analysis of prospective cohort studies. CMAJ. 2017;189:E711-720.
  8. Janket SJ, Manson JE, Sesso H, Buring JE, Liu S. A prospective study of sugar intake and risk of type 2 diabetes in women. Diabetes Care. 2003;26:1008-1015.

  9. Paynter NP, Yeh HC, Voutilainen S, et al. Coffee and sweetened beverage consumption and the risk of type 2 diabetes mellitus: the atherosclerosis risk in communities study. Am J Epidemiol. 2006;164:1075-1084.
  10. Palmer JR, Boggs DA, Krishnan S, Hu FB, Singer M, Rosenberg L. Sugar-sweetened beverages and incidence of type 2 diabetes mellitus in African American women. Arch Int Med. 2008;168:1487-1492.
  11. Nettleton JA, Lutsey PL, Wang Y, Lima JA, Michos ED, Jacobs DR Jr. Diet soda intake and risk of incident metabolic syndrome and type 2 diabetes in the Multi-Ethnic Study of Atherosclerosis (MESA). Diabetes Care. 2009;32:688-694.
  12. Meyer KA, Kushi LH, Jacobs DR Jr, Slavin J, Sellers TA, Folsom AR. Carbohydrates, dietary fiber, and incident type 2 diabetes in older women. Am J Clin Nutr. 2000;71:921-930.
  13. Montonen J, Jarvinen R, Knekt P, Heliovaara M, Reunanen A. Consumption of sweetened beverages and intakes of fructose and glucose predict type 2 diabetes occurrence. J Nutr. 2007 137:1447-1454. 
  14. Bazzano LA, Li TY, Joshipura KJ, Hu FB. Intake of fruit, vegetables, and fruit juices and risk of diabetes in women. Diabetes Care. 2008;31:1311-1317.

  15. Schulze MB, Manson JE, Ludwig DS, et al. Sugar-sweetened beverages, weight gain, and incidence of type 2 diabetes in young and middle-aged women. JAMA. 2004;292:927-934.
  16. Imamura F, O’Connor L, Ye Z, et al. Consumption of sugar sweetened beverages, artificially sweetened beverages, and fruit juice and incidence of type 2 diabetes: systematic review, meta-analysis, and estimation of population attributable fraction. BMJ. 2015;351:h3576.

ICNM Recap: Sugar, Fat, and Weight Loss

August 4, 2017   Dr. Neal Barnard   weight loss, diabetes


ICNM Recap: Sugar, Fat, and Weight Loss

Sugar isn’t a health food, even when it comes from Dr. Pepper. But removing meat and dairy products from your diet is also essential when it comes to weight loss and fighting heart disease, diabetes, and America’s other diet-related disease epidemics. At last week’s International Conference on Nutrition in Medicine (ICNM), I explained how a plant-based diet—fruits, vegetables, grains, and legumes—is the best bet for staying healthy. Take a look:

Read my interview in the Washingtonian about the controversy surrounding What the Health, a new documentary that challenges the standard American diet.

What the Health! NFL’s Trent Williams Goes Vegan!

July 21, 2017   Dr. Neal Barnard  


Trent Williams goes vegan

Congrats to NFL player Trent Williams who is going vegan to up his game for the 2017 football season! What inspired him? The new documentary What the Health, which I’m glad to be part of!

“I’m bettering my life,” Williams told the Washington Post about his decision to give up animal products. Many athletes are making the same decision, using a completely vegan diet to improve their performance, cut recovery times, and maximize their overall health.

Trent Williams goes vegan

And Williams is not the only Washington athlete to be inspired by What the Health. The Post reports “fellow 300-pound offensive linemen Arie Kouandjio and Isaiah Williams saw the documentary soon after and adjusted their eating habits, Kouandjio going full vegan and Williams committing to a pescatarian diet.”

I’m sure Isaiah will be inspired to go vegan soon! The good news is the team is right here in Washington, D.C., and our experts at the Physicians Committee’s headquarters and the Barnard Medical Center are glad to offer support!

If you’re an athlete interested in improving your performance with a plant-based diet, check out our Food Power for Athletes page.


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