You may have recently been hearing about the health effects of ultra-processed foods. What foods fall into this category, exactly?
Ultra-processed foods are:
-Industrially produced
-Ready to eat
-Low in bioactive compounds like fiber, vitamins, minerals and phytochemicals
-High in salt, saturated fat, sugar, refined carbohydrates and food additives
Examples are frozen meals, soft drinks, hot dogs, fast food, packaged cookies, candies, cakes and chips.
The Study
The research literature consistently shows that exercise
is important to our health but is variety of exercise important? A study published
recently in the British Medical Journal attempted to find out.
Over 110,000 subjects from Harvard’s Nurses’ Health Study and Health Professional Follow-up Study had their exercise monitored and were followed for up to 34 years. An exercise variety score was created based on spending at least 20 minutes per week engaged in a wide variety of exercise.
The results were interesting:
-When comparing subjects with the highest exercise variety score to the lowest, there was a 19% lower risk of all-cause mortality.
-This benefit was independent of total physical activity. In other words, no matter how much total exercise you were getting, variety was associated with lower mortality.
doi:10.1136/bmjmed-2025-001513
Take Home Message
There appears to be a strong benefit to mixing up your exercise routine. Alternate different forms of cardio like walking or run-walking with gym equipment like elliptical trainers and Stair Masters. You can also build variety by trying different sports like tennis, ice skating, golf or skiing.
Why is this important? The researchers in this investigation believe that there are distinct physiological effects from different physical activities. These include a variety of ventilatory responses, muscles used and different nerve pathways utilized. Therefore, each type of exercise has its own unique health benefits, so the more variety, the better.
The Study
Proponents of low fat diets and proponents of low carb diets have been battling it out for decades. This study wanted to find out which was better for risk of heart disease. Over 200,000 participants in Harvard’s Health Professional Follow-up Study, Nurses’ Health Study and Nurses’ Health Study 2 had their diet measured repeatedly and were followed for up to 32 years for incidence of coronary heart disease.
A scoring system was created for a healthy version of each diet (lean proteins, plant oils and unrefined grains) as well as an unhealthy version (fattier animal-based proteins, saturated fats and refined grains).
The results showed that when healthy foods were chosen, risk for heart disease decreased and when unhealthy foods were chosen, risk went up. In other words, the amount of carb or fat didn’t really matter, just the quality of the food that was consumed. A low carb diet could be protective or risky, as could a low fat diet.
doi: 10.1016/j.jacc.2025.12.038
Take Home Message
Whatever diet you are following, focus on healthy carbs (fruits, vegetables, whole grains and legumes), healthy fats (olive oil, nuts, avocados) and healthy proteins (lean meats, seafood and lots of plant protein like beans and lentils).
This study shows that you really don’t need to get too caught up on the percentages of protein, fat and carbohydrate. Just make good choices.
Step counters have become a common feature of wearable technology and many of us are tracking how many steps we are taking each day. This begs the question of just how many steps do we really need to improve our health? A common answer is 10,000 steps, but there isn’t a whole lot of science behind this number.
The Study
This interesting investigation appeared in JAMA Internal Medicine several years ago. 17,708 subjects with a mean baseline age of 72 years from the Women’s Health Study wore accelerometers for a 4 year follow up (Reference 1). By the end of this time, 504 women had died.
The women were split into quartiles depending on the average number of steps taken per day. The results were a bit surprising:
The 1st quartile averaged 2,718 steps per day and was the reference group (the group the other quartiles were compared to).
The 2nd quartile averaged 4,363 steps per day and had a 46% lower risk of death from any cause when compared to the 1st quartile.
The 3rd quartile averaged 5,905 steps per day and had a 53% lower risk of death from any cause.
The 4th quartile averaged 8,442 steps per day and had a 66% lower risk of death from any cause.
There were a couple of other surprising findings:
-The mortality benefit leveled off at 7,500 steps. Doing more than this
did not really improve risk of dying from any cause.
-Step intensity wasn’t particularly important. The number of steps is all that really mattered. In other words, how fast you walked did not appreciably impact the reduction in risk of dying from any cause.
Conclusions And Recommendations
I think it is great when fitness and nutrition theories are put to the
test of a well-designed research study.
A few take home messages:
-If your goal is general health improvement and chronic disease risk reduction, don’t worry about hitting 10,000 steps per day, 7,500 will get the job done.
-Don’t worry about how fast you are walking. It does not seem to matter all that much.
-If your goal is weight loss, higher intensity and longer duration of cardio is likely more important.
-It is not all or nothing. Although the sweet spot for improved health was 7,500 steps, significant benefit was found in subjects walking just over 4,000 steps per day.
References
1) JAMA Intern Med. 2019;179(8):1105-1112
The Study
There has been a very disturbing trend of increasing colon
cancer incidence in patients under the age of 50 in recent years. This study
tries to figure out one of the reasons why this is happening. 29,105 young
women from Harvard’s Nurses’ Health Study II cohort had their diet and
colonoscopy results monitored for a 24-year follow-up.
The results were compelling. When comparing subjects consuming the most ultra-processed foods to those consuming the least, there was a 45% increased risk of early onset colorectal conventional adenomas.
JAMA Oncol. doi:10.1001/jamaoncol.2025.4777
Take Home Message
Ultra-processed food are commercially produced food
products that are ready to eat and low in bioactive compounds such as fiber,
vitamins and polyphenols. They are usually high in unhealthy fats, refined
carbs, sodium and food additives.
In this cohort, the most common sources of ultra-processed foods were breads, breakfast foods, sauces, spreads and condiments.
The authors believed that these foods may disrupt gut microbiota and increase inflammation in the colon, leading to an increased risk of colon cancer.
Do your best to limit ultra-processed foods and eat your food in its whole and natural form.
The Study
Several fad diets claim that whole milk is a healthier
choice than low fat milk. A recent study put this theory to the test. A
Norwegian cohort of 73,860 subjects had their milk consumption measured and
were followed for 33 years.
The results were compelling:
Whole milk was associated with a statistically
significant increased risk of death from ischemic heart disease and all-cause
mortality.
When compared to whole milk, low fat milk was associated with a statistically significantly lower risk of cardiovascular mortality, death by ischemic heart disease, death by acute myocardial infarction and all-cause mortality.
American Journal of Clinical Nutrition 2025;122:1075-85.
Take Home Message
Whole milk contains high amounts of saturated fat, which
is known to be an unhealthy source of fat. Don’t let authors of fad diets books
distract you from decades of high quality research.
Shoot for low fat or fat free dairy products and choose healthy sources of fat such as olive oil, canola oil, nuts, nut butters, seeds and avocados.
Next up for review is Diet, Drugs And Dopamine by David Kessler, MD. The author is the former Commissioner of the Food and Drug Administration and is a graduate of Harvard Medical School.
Introduction
The main focus of
this book is the new class of weight loss drugs; the GLP-1 agonists such as
Wegovy and Zepbound. It contains chapters on the use of these drugs, side
effects, our current food environment and weight maintenance when you get off
the medication. The book is 385 pages. It is very well-written and I enjoyed
reading it.
3 Things I Really Liked About Diet, Drugs And Dopamine
1) I really like
how this book presents the advice of multiple experts and not just the author’s
opinions. Dr. Kessler includes quotes
from many of the world’s foremost clinicians and researchers in weight loss
medicine. This adds a lot to the book.
2) The author stresses that doctors are not providing the proper nutrition support for patients on the GLP-1 agonists. I couldn’t agree more. Most patients are eating between 500 and 800 calories a day on these medications. This is similar to what an anorexic patient eats in a day. There has been widespread signs of malnutrition in these patients and one expert even reported a case of scurvy in his office. Scurvy, in 2025!
3) The author also points out that up to 40% of weight lost by these patients is muscle mass. This can cause a host of problems and I like that the author stresses resistance training as an essential part of the program for these patients.
3 Things I Didn’t Agree With In Diet, Drugs And Dopamine
1) I feel like the book was a little longer
than it needed to be. If it was a bit more focused on the GLP-1 medicines, it would have been an easier read.
Sections on the history of food labels and nutritional biochemistry, for
example, were not really necessary in my opinion.
2) The author repeatedly states that lifestyle changes always fail for those trying to lose weight. I strongly disagree here. I have seen clients lose weight and keep it off for well over 20 years. Just because weight loss is not easy or quick does not mean it is not possible.
3) I wish the references were cited numerically in the text instead of just lumped together in the back of the book. I am sure most readers won’t notice or care about this, but as a nutrition researcher, I often will find a reference I want to download and it is much harder to find them this way.
Is Diet, Drugs And Dopamine Worth Reading?
Absolutely! The GLP-1 agonist meds have hit our world like a ton of
bricks and a lot is not known about them. This book provided a wealth of
information about how these drugs work, known and potential side effects and
some strategies about what to do when you go off of them. This is really
important, as up to 90% of patients stop taking them after 1 year (according to
one of the experts in the book).
I would strongly recommend this book to anyone taking these meds, thinking about taking them or any health care clinician working with these patients.
