One of the most startling findings is the notion of constrained daily energy expenditure. This is the idea that the human metabolism adapts to our activity levels to keep our daily calorie burn in a surprisingly narrow range — no matter how hard you work out
Now I understand how my low exercise levels during year one of the pandemic factored into my weight loss efforts. My metabolism reset and it spent calories on other life functions. Here’s the part of the interview that hit home for me. The quote refers to a recent television show The Biggest Loser.
Contestants went on this show and were put under a brutal routine of intense exercise, coupled with near starvation. You can lose a lot of weight that way. But it’s not sustainable. Your body pushes back hard by slashing its metabolic rate.
The Take Home Lesson
DO exercise for all of its associated health benefits. But exercising more is not exactly the best strategy for losing weight.
Herman Pontzer is an evolutionary anthropologist at Duke University. His theory argues that human metabolism has evolved to the point where how we eat and expend our calories is more important than what we eat. I think I’ll put his recent book on my list of books to read.
One study focused on almost 9,000 breast cancer survivors and asked the women about their diet every four years after their diagnosis. Over the follow-up period, averaging 11.5 years, women who ate more fruits and vegetables and women who ate more vegetables had a lower risk of dying from any cause than did women with lower intakes of these foods. Women with the highest intakes of vegetables and fruits averaged 7.4 servings per day; those with the lowest intake averaged 2.2 servings per day.
Farvid MS, Holmes MD, Chen WY, et al. Postdiagnostic fruit and vegetable consumption and breast cancer survival: prospective analyses in the Nurses’ Health Studies. Cancer Res. 2020;80(22):5134-5143.
Total fruit and vegetable intake was associated with a reduced risk of frailty with those averaging seven or more servings of fruits and vegetables daily having a lower risk than those averaging fewer than three servings a day. Leafy green vegetables, yellow and orange vegetables, and apples and pears were specific fruits and vegetables associated with a lower risk.
Fung TT, Struijk EA, Rodriguez-Artalejo F, Willett WC, Lopez-Garcia E. Fruit and vegetable intake and risk of frailty in women 60 years old or older. Am J Clin Nutr. 2020 [published online ahead of print].
The quotes above are just two of the studies profiled in the Vegetarian Journal’s most recent scientific update. Unfortunately the citations are not links to the original studies. Here is the link to the full Vegetarian Journal Scientific Update:
Researchers have found that eating disorder behaviors, such as binge-eating, alter the brain’s reward response process and food intake control circuitry, which can reinforce these behaviors. Understanding how eating disorder behaviors and neurobiology interact can shed light on why these disorders often become chronic and could aid in the future development of treatments. The study, published in JAMA Psychiatry, was supported by the National Institutes of Health.
Incidence of early-onset colorectal cancer (EO-CRC, diagnosed under age 50 years) has been on the rise in many high-income countries over the past two decades.
Sugar-sweetened beverages (SSBs) can exert adverse metabolic repercussions throughout the life course, including childhood and adulthood obesity and type 2 diabetes.
Despite the highest level of SSB consumption being characterised among adolescents and young adults, the association between SSBs and EO-CRC has not been investigated.
What are the new findings?
Compared with <1 serving/week of SSB consumption, higher intake (ie, ≥2 servings/day) in adulthood was associated with a 2.2-fold higher risk of EO-CRC.
Each serving/day increment of SSB intake at age 13–18 years was associated with a 32% higher risk of EO-CRC.
Hur J, Otegbeye E, Joh H, et al Sugar-sweetened beverage intake in adulthood and adolescence and risk of early-onset colorectal cancer among women Gut Published Online First: 06 May 2021. doi: 10.1136/gutjnl-2020-323450
Watch your sugar intake! Don’t think too long about that colonoscopy your doctor recommended. If you have a family history of colorectal cancer don’t think about getting tested, do it. I lost a first cousin to metastatic colon cancer.
Previous studies looking at blood sugar after eating have focused on the way that levels rise and fall in the first two hours after a meal, known as a blood sugar peak. However, after analyzing the data, the PREDICT team noticed that some people experienced significant ‘sugar dips’ 2-4 hours after this initial peak, where their blood sugar levels fell rapidly below baseline before coming back up.
Big dippers had a 9% increase in hunger, and waited around half an hour less, on average, before their next meal than little dippers, even though they ate exactly the same meals.
Big dippers also ate 75 more calories in the 3-4 hours after breakfast and around 312 calories more over the whole day than little dippers. This kind of pattern could potentially turn into 20 pounds of weight gain over a year.
Five servings of fruits and vegetables a day — in particular, three vegetables and two fruits — provide the greatest mortality benefit, according to an observational study and meta-analysis in Circulation.
Researchers analyzed results from the Nurses’ Health Study and Health Professionals Follow-Up Study. Over 100,000 people regularly completed food-frequency questionnaires and were followed for up to 30 years. During that time, nearly a third of participants died.
After multivariable adjustment, the greatest mortality benefit was seen for five servings of produce a day, compared with two servings (hazard ratio, 0.88). Eating more than five servings a day was not associated with greater risk reductions.