The latest Dietary Guidelines issued by the government promote beef tallow as a healthy fat choice. This was a surprising recommendation because it is loaded with saturated fat, which has been shown to increase the risk of heart disease and stroke consistently in the research literature.
Healthier sources of fat have been shown to actually decrease risk of heart disease and stroke. These include olive oil, canola oil, nuts, seeds and avocados. These are the fats you should be choosing.
The Study
EPA and DHA are long chain fatty acids in the Omega 3 family. Good sources are salmon, sardines, tuna, mackerel and herring. They have a lot of health benefits. In this interesting study, 557 eight year olds from Singapore had their fasting long chain fatty acids measured by nuclear magnetic resonance spectroscopy. Their diets were also measured by means of a validated food frequency questionnaire at age 7.
Academic performance was measured by the Wechsler Individual Achievement Test III at age 9 and at age 12, their primary school final examination scores were obtained.
The percent of long chain fatty acids was associated with higher reading fluency, better spelling and significantly greater scores on their primary school final exams.
American Journal of Clinical Nutrition 2026;123:101233
Take Home Message
There is more and more research showing that our diet influences our brain function. This can often translate to improved academic or work performance when making the right dietary choices. Although word has gotten out somewhat in the last few years, I am not sure that people fully realize how what we eat shapes every facet of our lives.
The Study
The use of diet beverages to support weight loss remains controversial. In this interesting investigation that combined Harvard’s Nurses’ Health Study, Nurses Health Study 2 and Health Professional Follow-up Study, over 143,000 subjects had their diet and weight tracked for 28 years. The goal of this study was to see if diet soda helped people lose weight.
Here are some of the major findings:
-For every 4 year measurement period, subjects gained an
average of about 3 pounds.
-Each 3 serving per week increase in diet soda consumption resulted in a small but significant weight loss during each 4 year measurement period. The association was strongest for the obese and heavy sugar soda drinkers.
-Replacing 3 sugar soda beverages with diet beverages each week was associated with a 3 pound weight loss every 4 year measurement period.
-This was the same as substituting 3 sugar soda beverages with water.
American Journal of Clinical Nutrition 2026; 123:101261
Take Home Message
This study shows that over the long haul, drinking diet soda instead of regular soda is associated with improved body weight. This may seem like common sense to a lot of you, but many researchers have argued in the past that diet soda does not aid in weight loss and may even result in weight gain.
No one is considering diet soda a health food and drinking it all the time is a bad idea. However, the occasional diet soda or sugar free treat will allow you to stay away from sugar and this will make weight loss a lot easier.
Use of GLP-1 medications is becoming common to treat obesity. Recent reports show that 6% of the US adult population is using GLP-1 therapy and 12% are currently using it or have in the past (Reference 1). It has quickly become clear that GLP-1 patients have nutrition and exercise needs that are not being met.
A joint advisory from several nutrition and obesity societies was recently published in the American Journal Of Clinical Nutrition. (Reference 2).
The Study
This joint advisory was comprehensive and very well put together. Here are some of the most important take home messages:
-Research is showing that GLP-1 users cut their calories so severely that nutrient deficiencies often develop. The most likely deficiencies are iron, calcium, magnesium, zinc, Vitamins A, D, E, K, B1, B12 and C.
-Such a dramatic reduction in calories (up to 40%) results in very rapid weight loss which contributes to muscle and bone loss. One trial cited in the advisory showed that 40% of weight lost by GLP-1 users was lean body mass.
-Another interesting finding is that 67% of patients stop using the medication after 1 year and 85% after 2 years. This is a problem because it looks like lost weight comes back on quickly after stopping this medication.
Conclusions And Recommendations
For many people, the GLP-1’s have been a godsend. However, as with any medication, it must be taken properly. In many cases, doctors are just prescribing this medication and letting people go out into the world and basically starve themselves. This has been a disaster.
Here are a few very important take home messages for those taking GLP-1’s:
-Don’t starve yourself. Be sure to track your calories. Women should not be eating less than 1,200 calories per day. Men should not be eating less than 1,500 calories per day.
-Many GLP-1 users have the idea that because they are losing weight, they can eat whatever they want, just less of it. This is not the case. Because calories are so restricted, you have to ensure that the dramatically reduced amount of food you are eating is packed with nutrients. Otherwise, you will risk nutrient deficiencies.
-It is crucial to lift weights when you are on these medications. This is essential to preserve muscle and bone during the weight loss process.
-Lastly, prepare for life without these medications. Although people are supposed to stay on these meds for life, 85% stop taking them after 2 years. This is for a variety of reasons, including cost, side effects or decreased efficacy. Make sure you are preparing a diet, cardio and strength program to keep lost weight off if the medication is discontinued.
References
1) A. Montero, G. Sparks, M. Presiado et al. KFF Health Tracking Poll May 2024: The public’s use and views of GLP-1 drugs, Kaiser Family Foundation (KFF), 2021.
2) Mozaffarian D, Agarwal M, Aggarwal M et al. Nutrition priorities to support GLP-1 therapy for obesity: A joint advisory. American Journal of Clinical Nutrition 2025: 122:344-67
Ultra-processed foods are industrially produced, ready to eat foods 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.
Ultra-processed foods have been investigated extensively in the research literature.
They have been found to have a negative impact on:
-Body mass index
-Waist size
-Risk of
hypertension
-Risk of insulin
resistance
-Risk high
triglycerides
-Risk of heart
disease
-Risk of stroke
-Risk of type 2
diabetes
-Risk of cancer
It goes without saying that these foods should be strictly limited.
The Study
The research tends to go back and forth on the necessity
of taking a multivitamin. In this interesting study, over 900 participants from
Harvard’s COSMOS randomized trial took a multivitamin (Centrum Silver) for 2
years and had measures of biological aging (DNA methylation) taken at the start
and end of follow-up.
By the end of the study, there was a small but significant difference in biological aging for subjects taking the multivitamin.
Nature Medicine 2026;32:1012-1022
Take Home Message
While this is
preliminary research, it is pretty exciting to see evidence that taking a
multivitamin every day can slow down the effects of aging on our bodies. Stay
tuned for more definitive research on this subject.
The Study
For decades, coffee and caffeine were considered
unhealthy habits. However, as research methods started to improve in the last 30
years or so, opinions are changing fast. In this interesting study, 131,821
subjects from Harvard’s Nurses’ Health Study and Health Professional Follow-up
Study had their coffee drinking habits measured and were followed for up to 43
years. They were also followed for a diagnosis of dementia.
The results were compelling:
-When comparing subjects who consumed the most caffeinated coffee to subjects consumed the least, there was an 18% lower risk of dementia.
-Higher consumption of caffeinated tea showed similar cognitive benefits.
-2 to 3 cups of coffee per day (or 1 to 2 cups of tea) offered the most pronounced benefit.
-Interestingly, decaf coffee was not associated with cognitive protection.
doi:10.1001/jama.2025.27259
Take Home Message
Coffee contains polyphenols and caffeine which may be
neuroprotective. In this study, decaf coffee did not seem to have much of an
effect, so caffeine may just be the important component.
Either way, if you enjoy coffee, it is nice to know that this habit may also lower your risk of cognitive decline.
