This article was previously published February 27, 2019, and has been updated with new information.
The struggle with weight gain and obesity is a common and costly health issue, leading to an increase in risk for heart disease, Type 2 diabetes and cancer, just to name a few.
According to CDC figures for 2017-18, 19.3% of American children1 and 42.4% of adults2 are now obese, not just overweight. That’s a significant increase over the 1999/2000 rates, when just under 16% of children ages 6 to 193 and 30.5% of adults were obese.
Research has linked growing waistlines to a number of different sources, including processed foods, sodas and high-carbohydrate diets. Risks associated with belly fat in aging adults includes an elevated risk of cardiovascular disease and cancer.4
Researchers have actually predicted obesity will overtake smoking as a leading cause of cancer deaths,5 and recent statistics suggest we’re well on our way to seeing that prediction come true as obesity among our youth is triggering a steep rise in obesity-related cancers at ever-younger ages.
Millennials More Prone to Obesity-Related Cancers
As obesity rates rise, so do related health problems, including cancer. According to a report6 published in 2014 on the global cancer burden, obesity is already responsible for an estimated 500,000 cancer cases worldwide each year, and that number is likely to rise further in coming decades.
As reported in a Lancet study7 by the American Cancer Society, rates of obesity-related cancers are rising at a far steeper rate among millennials than among baby boomers. According to the authors,8 this is the first study to systematically examine obesity-related cancer trends among young Americans.
What’s more, while six of 12 obesity-related cancers (endometrial, gallbladder, kidney, multiple myeloma and pancreatic cancer) are on the rise, only two of 18 cancers unrelated to obesity are increasing. As noted in the press release:9
“The obesity epidemic over the past 40 years has led to younger generations experiencing an earlier and longer lasting exposure to excess adiposity over their lifetime than previous generations.
Excess body weight is a known carcinogen, associated with more than a dozen cancers and suspected in several more … Investigators led by Hyuna Sung, Ph.D., analyzed 20 years of incidence data (1995-2014) for 30 cancers … covering 67 percent of the population of the U.S. …
Incidence increased for 6 of the 12 obesity-related cancers … in young adults and in successively younger birth cohorts in a stepwise manner. For example, the risk of colorectal, uterine corpus [endometrial], pancreas and gallbladder cancers in millennials is about double the rate baby boomers had at the same age …
‘Although the absolute risk of these cancers is small in younger adults, these findings have important public health implications,’ said Ahmedin Jemal, D.V.M., Ph.D., scientific vice president of surveillance [and] health services research and senior/corresponding author of the paper.
‘Given the large increase in the prevalence of overweight and obesity among young people and increasing risks of obesity-related cancers in contemporary birth cohorts, the future burden of these cancers could worsen as younger cohorts age, potentially halting or reversing the progress achieved in reducing cancer mortality over the past several decades.
Cancer trends in young adults often serve as a sentinel for the future disease burden in older adults, among whom most cancer occurs.'”
Changes in Diet Are Driving the Obesity Epidemic
Studies10,11,12 have repeatedly demonstrated that when people switch from a traditional whole food diet to processed foods (which are high in refined flour, processed sugar and harmful vegetable oils), disease inevitably follows.
Below are just a few telling statistics. For more, see nutrition researcher Kris Gunnars’ 11 graphs published in Business Insider showing “what’s wrong with the modern diet.”13
Over the past 200 years, our sugar intake has risen from 2 pounds to 152 pounds per year.14 While Americans are advised to get only 10% of their calories from sugar,15 equating to about 13 teaspoons a day for a 2,000-calorie diet, the average intake is 42.5 teaspoons per day.16 It’s important to realize that it’s nearly impossible to achieve that on a processed food diet.
Not only that, you can’t exercise off the excess calories. For example, to burn off the calories in a single 12-ounce soda, you’d have to walk briskly for 35 minutes. To burn off a piece of apple pie, you’d be looking at a 75-minute walk.17
Soda and fruit juice consumption is particularly harmful, studies18,19 show, raising a child’s risk of obesity by 60% per daily serving.20 Research has also shown refined high-carb diets in general are as risky as smoking, increasing your risk for lung cancer by as much as 49%.21
Between 1970 and 2009, daily calorie intake rose by an average of 425 calories, a 20% increase, according to Stephan Guyenet, Ph.D.,22 who studies the neuroscience of obesity. This rise is largely driven by increased sugar and processed food consumption, and the routine advertising of junk food to children.23
To attract customers and compete with other restaurants, companies often add salt, sugar, fat and flavor chemicals to trigger your appetite. Unfortunately, it turns out additives and chemicals supplemented in processing kill off beneficial gut bacteria, which further exacerbates the problems created by a processed food diet.24
According to epidemiology professor Tim Spector, even eating a relatively small number of highly processed ingredients is toxic to your gut microbiome, which start to die off just days after a eating a fast food heavy diet, suggesting excess calories from fast food may not be the only factor to blame for rising weight.
Processed vegetable oils, which are high in damaged omega-6 fats, are another important factor in chronic ill health. Aside from sugar, vegetable oils are a staple in processed foods, which is yet another reason why processed food diets are associated with higher rates of heart disease and other diseases.
Soybean oil, which is the most commonly consumed fat in the U.S.,25 has also been shown to play a significant role in obesity and diabetes, actually upregulating genes involved in obesity. Remarkably, soybean oil was found to be more obesogenic than fructose!
“Ultraprocessed diets cause excess calorie intake and weight gain,” research26 concludes, showing that when people are allowed to eat as much as they want of either ultraprocessed foods or unprocessed food, their energy intake is far greater when eating processed fare.
In just two weeks, participants gained between 0.3 and 0.8 kilos (0.166 and 1.76 pounds) on the ultraprocessed diet, and lost 0.3 to 1.1 kilos (0.66 to 2.42 pounds) when eating unprocessed food.
As These Foods Became the Norm, so Did Chronic Illness
Unfortunately, Americans not only eat a preponderance of processed food, but 60% of it is ultraprocessed27 — products at the far end of the “significantly altered” spectrum, or what you could typically purchase at a gas station.
The developed world in general eats significant amounts of processed food, and disease statistics reveal the inherent folly of this trend. There’s really no doubt that decreasing your sugar consumption is at the top of the list if you’re overweight, insulin resistant, or struggle with any chronic disease.
It’s been estimated that as much as 40% of American health care expenditures are for diseases directly related to the overconsumption of sugar.28 In the U.S., more than $1 trillion is spent on treating sugar and junk food-related diseases each year.29
Any foods that aren’t whole foods directly from the vine, ground, bush or tree are considered processed. Depending on the amount of change the food undergoes, processing may be minimal or significant. For instance, frozen fruit is usually minimally processed, while pizza, soda, chips and microwave meals are ultraprocessed foods.
The difference in the amount of sugar between foods that are ultraprocessed and minimally processed is dramatic. Research30 has demonstrated that over 21% of calories in ultraprocessed foods comes from sugar, while unprocessed foods contain no refined or added sugar.
In a cross-sectional study31 using data from the National Health and Nutrition Examination Survey of over 9,000 participants, researchers concluded that “decreasing the consumption of ultraprocessed foods could be an effective way of reducing the excessive intake of added sugars in the USA.”
Definition of Ultraprocessed Food
As a general rule, ultraprocessed foods can be defined as food products containing one or more of the following:
Ingredients that are not traditionally used in cooking.
Unnaturally high amounts of sugar, salt, processed industrial oils and unhealthy fats.
Artificial flavors, colors, sweeteners and other additives that imitate sensorial qualities of unprocessed or minimally processed foods (examples include additives that create textures and pleasing mouth-feel).
Processing aids such as carbonating, firming, bulking, antibulking, defoaming, anticaking, glazing agents, emulsifiers, sequestrants and humectants.
Preservatives and chemicals that impart an unnaturally long shelf-life.
Genetically engineered ingredients, which in addition to carrying potential health risks also tend to be heavily contaminated with toxic herbicides such as glyphosate, 2,4-D and dicamba.
As described in the NOVA classification of food processing,32 “A multitude of sequences of processes is used to combine the usually many ingredients and to create the final product (hence ‘ultraprocessed’).” Examples include hydrogenation, hydrolysation, extrusion, molding and preprocessing for frying.
Ultraprocessed foods also tend to be far more addictive than other foods, thanks to high amounts of sugar (a substance shown to be more addictive than cocaine33), salt and fat. The processed food industry has also developed “craveabilty” into an art form. Nothing is left to chance, and by making their foods addictive, manufacturers ensure repeat sales.
Processed Food Diet Linked to Early Death
In related news, recent research34 involving more than 44,000 people followed for seven years warns that ultraprocessed foods raise your risk of early death. The French team looked at how much of each person’s diet was made up of ultraprocessed foods, and found that for each 10% increase in the amount of ultraprocessed food consumed, the risk of death rose by 14%.
This link remained even after taking confounding factors such as smoking, obesity and low educational background into account. As you’d expect, the primary factors driving the increased death rate was chronic diseases such as heart disease and cancer.
Nita Forouhi, a professor at the MRC Epidemiology Unit at the University of Cambridge, who was not part of the study, told The Guardian:35
“The case against highly processed foods is mounting up, with this study adding importantly to a growing body of evidence on the health harms of ultraprocessed foods … [W]e would ignore these findings at public health’s peril.
A vital takeaway message is that consumption of highly processed foods reflects social inequalities — they are consumed disproportionately more by individuals with lower incomes or education levels, or those living alone.
Such foods are attractive because they tend to be cheaper, are highly palatable due to high sugar, salt and saturated fat content, are widely available, highly marketed, ready to eat, and their use-by dates are lengthy, so they last longer. More needs to be done to address these inequalities.”
Ultraprocessed Foods Linked to Cancer
Another French study36,37 published last year also found that those who eat more ultraprocessed food have higher rates of obesity, heart problems, diabetes and cancer. Nearly 105,000 study participants, a majority of whom were middle-aged women, were followed for an average of five years.
On average, 18% of their diet was ultraprocessed, and the results showed that each 10% increase in ultraprocessed food raised the cancer rate by 12%, which worked out to nine additional cancer cases per 10,000 people per year.
The risk of breast cancer specifically went up by 11% for every 10% increase in ultraprocessed food. Sugary drinks, fatty foods and sauces were most strongly associated with cancer in general, while sugary foods had the strongest correlation to breast cancer.
According to the authors, “These results suggest that the rapidly increasing consumption of ultraprocessed foods may drive an increasing burden of cancer in the next decades.” Study co-author Mathilde Touvier told CNN:38
“It was quite surprising, the strength of the results. They were really strongly associated, and we did many sensitive analysis and adjusted the findings for many cofactors, and still, the results here were quite concerning.”
Diet Is a Key Factor Determining Your Health and Longevity
Research39 published in 2017 linked poor diet to an increased risk of cardiometabolic mortality (death resulting from Type 2 diabetes, heart disease and stroke).
According to the authors, suboptimal intake of key foods such as fruits, vegetables, nuts and seeds, and animal-based omega-3, along with excessive consumption of processed foods such as meats and sugar-sweetened beverages accounted for more than 45% of all cardiometabolic deaths in 2012. In other words, the more processed foods you eat, and the less whole foods you consume, the greater your risk of chronic disease and death.
Other research published that same year found that eating fried potatoes (such as french fries, hash browns and potato chips) two or more times per week may double your risk of death from all causes.40 Eating potatoes that were not fried was not linked to an increase in mortality risk, suggesting frying — and most likely the choice of oil — is the main problem.
In a 2013 presentation41 at the European Ministerial Conference on Nutrition and Noncommunicable Diseases by Dr. Carlos Monteiro,42 professor of nutrition and public health at the University of Sao Paulo, Brazil, Monteiro stresses the importance of creating “policies aiming the reformulation of processed foods,” and limiting children’s exposure to junk food marketing, in order to tackle the rise in diet-related noncommunicable diseases.
In my view, eating a diet consisting of 90% real food and only 10% or less processed foods is an achievable goal for most that could make a significant difference in your weight and overall health. You simply need to make the commitment and place a high priority on it. To get started, consider the following guidelines:
Focus on raw, fresh foods, and avoid as many processed foods as possible (if it comes in a can, bottle or package, and has a list of ingredients, it’s processed).
Severely restrict carbohydrates from refined sugars, fructose and processed grains.
Increase healthy fat consumption. (Eating dietary fat isn’t what’s making you pack on pounds. It’s the sugar/fructose and grains that add the padding.)
You may eat an unlimited amount of nonstarchy vegetables. Because they are so low in calories, the majority of the food on your plate should be vegetables.
Limit protein to less than 0.5 gram per pound of lean body weight.
Replace sodas and other sweetened beverages with pure, filtered water.
Shop around the perimeter of the grocery store where most of the whole foods reside, such as meat, fruits, vegetables, eggs and cheese. Not everything around the perimeter is healthy, but you’ll avoid many of the ultraprocessed foods this way.
Vary the whole foods you purchase and the way you eat them. For instance, carrots and peppers are tasty dipped in hummus. You get the crunch of the vegetable and smooth texture of the hummus to satisfy your taste, your brain and your physical health.
Stress creates a physical craving for fats and sugar that may drive your addictive, stress-eating behavior. If you can recognize when you’re getting stressed and find another means of relieving the emotion, your eating habits will likely improve.
The Emotional Freedom Techniques (EFT) can help reduce your perceived stress, change your eating habits around stress and help you create new, healthier eating habits that support your long-term health. To discover more about EFT, watch the video at this referenced link on substack.43
Analysis by Dr. Joseph Mercola