In science, the journey from a theory to a well-understood fact isn’t always straightforward. It often starts with a hunch – something scientists have noticed but just don’t fully understand yet. That hunch is tested from every angle, again and again. Sometimes for years, sometimes for centuries, until it becomes a model for what’s actually going on.
For doctors who treat obesity, one of these ever-evolving theories is the “protein leverage hypothesis” or “protein leverage model.” Basically, it argues that appetite isn’t just determined by how much we eat, but by what we eat. We’re hard-wired for protein, and our body doesn’t want to turn that appetite off until it gets enough of it. In other words, when we eat less protein, we tend to eat more of everything else.
This wasn’t a problem for most of human history. If we didn’t get enough protein, we made up for it with larger quantities of vegetables and grains. But since the 1970s, those protein substitutes have been steadily replaced with over-processed foods high in sugar, carbohydrates, and fats. Not only that, but protein is relatively expensive, while processed foods are not. So in developing areas, this issue can be compounded by poverty.
To what extent protein leverage has contributed to the obesity epidemic is still unclear. There’s some evidence proving elements of the hypothesis, but nothing that conclusively shows it’s a leading cause. One of the reasons some scientists are skeptical is that the overall percentage of protein in our food supply has risen over the last century. So we’re eating more protein than ever, right?
Kind of. While the overall protein content in our diet has risen, the actual percentage of calories from protein has decreased by 1% due to the even greater rise in available carbohydrates and fats. Researcher Kevin D. Hall recently showed that the 1% decrease actually raises our overall calorie intake significantly. I won’t go into the math here, but his work seems to show that protein leverage may have contributed to as much as a third of the average adult weight gain over recent decades. Of course, it’s not the only contributor. Lifestyle and environment changes play their roles as well.
What does protein leverage mean for the average person trying to lose weight? Well, it reinforces a fundamental idea: that we should be more mindful of the things we eat. By understanding the sources of our nutrition – especially protein – we may be able to control appetite more effectively. When developing a strategy with your doctor, make sure that healthy sources of protein take center stage.
As we study the protein leverage model more closely, we’ll understand obesity better. But more importantly, we’ll be able to develop treatment plans that work with our bodies’ natural priorities. By listening to what our bodies tell us, the road to weight loss can be just a little bit easier.
Millions of people use step trackers as a way to meet their goal of walking 10,000 steps a day for better health and fitness.
But what’s so magic about this number? Is it actually based on science?
Turns out it isn’t.
In fact, its origins date back to 1964 when a Japanese company marketed the world’s first pedometer, a device called a manpo-kei, which translates as “10,000-step metre.” Over the next half century that widely promoted step goal became seen as the ideal to strive for.
Eventually, studies confirmed that people who engage in this number of daily steps do indeed have lower blood pressure, more stable glucose levels and happier moods.
No wonder that number found its way onto the wrists of FitBit users around the world.
But now some research indicates that number may be too high. For example, a research study from Harvard Medical School examining the data on 17,000 older women who did 4,500 daily steps found they were about 40 percent less likely to have died than those who managed only 2,700 steps.
Other research indicates that number may be too low. A small study of Scottish postal workers reported in the International Journal of Obesity found those who walked an average of 15,000 steps had a lower risk of heart disease, healthy cholesterol levels and trim waistlines.
Currently, the average number of steps for the U.S. adult population is between 4,000 and 5,000 steps a day.
So what’s the ideal number of steps?
There’s nothing wrong with aiming for 10,000 steps a day but it may be a problematic goal for a number of reasons. First, it doesn’t take into account the intensity of exercise—there’s a big difference between sauntering and walking at a quick stride, for example. Slow steps aren’t going to get your heart pumping, which is essential for keeping fit.
Speed walking or running in short bursts can offer more health benefits than walking for an extended time.
Also some fitness activities, such as yoga and weight training, can’t be quantified in steps.
Finally, setting an arbitrary goal of a certain number of daily steps may cause some people to stop walking once they reach that threshold, even if they might benefit from more activity.
The fact is, there’s nothing magical about walking 10,000 steps a day. What’s most important is being regularly active. Your best bet when it comes to walking is to establish a baseline to determine how many steps you currently take and then continuously increase that by setting new goals that are ambitious but attainable.
And remember, every step really does count.
Why is it that some people seem to gain weight by just looking at a piece of cake, while others can pack away large meals without packing on the pounds?
It doesn’t seem fair, but the fact is leanness comes naturally to some. And now a comprehensive new study on the genetics of obesity reveals why this might be so. The researchers identified rare gene variants that protect some lucky carriers from gaining weight.
The researchers examined mutations within genes that were associated with a lower or higher body mass index (BMI), the most reliable measure of obesity. They found 16 genes tied to BMI, some of which are expressed in the hypothalamus, the area of the brain that regulates hunger and metabolism. Those who carried variants that inactivate one of these genes—GPR75—weighed an average of 5.3 kilograms less and had half the odds of being obese compared to those with working copies of the gene. The variants that inactivate this gene are thought to be quite rare with only one in 3,000 people carrying it.
One of the impacts of this finding is that the discovery of these rare variants could lead to new medication treatments for people struggling with obesity.
And that’s good news because obesity is an epidemic. In the U.S. more than 40 percent of the population is considered obese (in Canada it’s closer to 30 percent).
At least 2.8 million people die every year from being overweight or clinically obese. Obesity increases the risk of developing type 2 diabetes, heart disease, some cancers, and even severe COVID-19.
So is DNA destiny when it comes to gaining weight? There are many factors that determine a person’s chances of being obese, including diet, exercise and ill health. A healthy diet and regular exercise can offset a genetic predisposition but these people may have to work harder to maintain a normal weight.
Approximately 10 percent of a person’s obesity risk may be determined by their DNA, according to the authors of a 2019 study published in the journal Cell, which examined data from 2.1 million genetic variants to identify adults at risk of severe obesity.
The researchers found that a genetic predisposition to obesity begins to appear in early childhood and is often clearly evident by early adulthood — suggesting an opportunity for early intervention.
“We’ve known for a long time that some people are born with DNA predisposing them to obesity,” says one of the study authors, Dr. Amit V. Khera, a clinician and researcher at the Massachusetts General Hospital Center for Genomic Medicine. “Now, we can quantify those differences in a meaningful way, and potentially explore new routes for achieving better health.”
Fresh from my time at Obesity Week 2019, I came across a compelling op-ed in the Globe and Mail by Sasha High, medical director of the High Metabolic Clinic in Mississauga. Commenting on a recent fat-shaming Golden Globes segment by talk show host James Corden, Sasha passionately argues for a shift in our perception of people suffering from obesity in order to change how we approach its treatment and management. Despite the advances in obesity management and treatment, and its recognition as a disease, she claims its patients continue to suffer discrimation. This stigmatization redirects ‘blame’ onto patients, and creates a culture of discrimination that permeates every aspect of their lives, impacting not only their physical, but also mental health.
In addition to the personal impact, these negative perceptions of obesity, known as weight or obesity bias, also have important ramifications for the diagnosis and management of obesity and its comorbidities. A recent study from Fruh et al. (2017) in the UK reported a significant prevalence of obesity bias amongst primary care physicians. More than 50% of physicians surveyed reported perceiving obese patients as “awkward, unattractive, ugly, and non-compliant” and having spent less time with these patients than thinner patients.
Why are these figures important? As Sasha bluntly points out in her op-ed, fat-shaming should have no place in obesity treatment. Enacted stigma on the part of primary care physicians has critical ramifications for patients, and can reduce the quality and availability of patient-centred care. As physicians, it would be taboo to treat a patient with cancer or coronary disease with contempt; yet patients suffering from obesity often fail to receive the same consideration. The perpetuation of these negative stereotypes creates a hostile environment that can hamper diagnosis and treatment. Patients can recognize this negative bias against them, and the deterioration of the bond between patient and provider not only makes the patients less likely to seek out treatment, but also can decrease adherence to management recommendations, making treatment less effective and exacerbating the development of more severe comorbid diseases.
Our society as a whole requires a profound change in the way we approach and inherently stigmatize weight. While this paradigm shift will require more collaborative action across multiple sectors of society, as physicians we can do our part by working to create a more supportive and understanding environment for our patients. Easy steps to combating obesity bias in our own practice and offices include:
- Use language and terminology that patients are comfortable with when discussing weight
- Employ sensitive weighing procedures
- Practice bias-free treatment approaches
- Provide medical equipment (i.e. gowns, office chairs, etc) that can accomodate for larger sized persons
And the last, but perhaps the most important step we can implement in our practice? Recognize our own implicit bias. Self-awareness is the first step in change, and it is critical that we are conscious of our own attitudes and values in order to avoid alienating our patients and ensuring that we are providing the highest quality of care.
Alarmed by the number you’re seeing on your bathroom scale? You aren’t alone. Almost half of all adults say they’ve been eating more during the pandemic.
The term “COVID-15” has gained popularity as a variation on the “Freshman 15” many students gain during their first year of university. But it turns out that number may actually be too low.
According to the American Psychological Association’s annual “Stress in America” report, 40% of Americans have gained unwanted weight during the pandemic, with the average gain being a whopping 29 pounds (50% of those who reported undesired weight gain said they had gained more than 15 pounds, and 10% said they had gained more than 50 pounds).
Is it any wonder many of us are tipping the scales? We’ve been stuck at home for well over a year, with few opportunities to socialize, our schedules are off, gyms are closed and cooking and baking are among the few activities keeping us occupied.
Consider that the hashtag #stressbaking has 53,000 posts on Instagram.
The pandemic has us worried, bored, lonely, sad and stressed—all factors that can make us turn to food for comfort.
Because these unsettling emotions can be difficult to deal with, it’s tempting to seek out things to make ourselves feel better. That might be an extra glass or two of wine at night, too many Netflix shows, excessive online shopping — or repeatedly staring into the fridge or pantry for something yummy to eat.
As we reported in our last post, children are also gaining extra weight during the pandemic, due to missing physical education classes thanks to school closures, a lack of after-school sports activities and even just playing outside with friends. Studies show screen time for kids has doubled during the pandemic.
Even our pets are getting heavier. The Wall Street Journal reported that the largest chain of vet practices in the U.S. conducted a survey that revealed 42% of pet dogs and cats had gained weight during the pandemic.
Extra pounds aren’t easy to lose—for adults, children or pets—and they are cause for concern since significant weight gain poses long-term health risks. Just adding an extra 11 pounds can put you at higher risk of developing coronary heart disease and Type 2 diabetes. An extra 25 pounds put you at higher risk of stroke.
So what can you do to get a handle on pandemic weight gain? Here are a some tips to consider:
- Think before you eat: Ask yourself if you are actually hungry. Maybe you are just bored—or thirsty.
- Keep a food diary: Write down what you eat and see if there’s a connection between food and mood
- Keep it on the regular: Schedule your mealtimes.
- Avoid after-dinner snacking. Shut off the TV and go to bed earlier with a good book.
- Healthy food choices begin in the grocery store: If you don’t bring junk food home you won’t have it on hand when you get a hankering for something unhealthy.
- Allow yourself an occasional “treat” so you don’t feel too deprived. Keep healthier snacks on hand, such as fresh fruit, veggies and low-fat dip, nuts and popcorn.
- Distract yourself with a stress-relieving activity, such as listening to your favourite tunes, connecting with a friend, going for a walk or stretching.
- Don’t’ drink your calories: Nearly 25% of respondents in the Stress in America report said they are drinking more alcohol to cope with stress amid the pandemic.
- Make mealtime a pleasant event: If you can, eat with someone in person (or by FaceTime or Zoom) rather than chowing down alone in front of the tube.
- Eat mindfully: Allow yourself to fully enjoy your food. Focus on what you are eating and eat slowly, being sure to savour every single bite.