Protein-rich breakfast boosts satiety and concentration.

Study explores the link between diet and cognitive function, and the results reveal that a protein-rich breakfast can increase satiety and improve concentration
Study explores the link between diet and cognitive function, and the results reveal that a protein-rich breakfast can increase satiety and improve concentration

A new Danish study has explored the link between diet and cognitive function, and the results reveal that a protein-rich breakfast can increase satiety and improve concentration. This is important knowledge in a society with increasing obesity rates and lifestyle-related diseases, says researcher.

“Breakfast is the most important meal of the day.” This is a well-worn platitude that has never had much basis in scientific evidence.

But a new Danish study has explored how different types of breakfast affect satiety and concentration and it has added new fuel to the old cliché.

The study followed 30 obese women aged 18 to 30 for three days, during which the women consumed a protein-rich breakfast, a carbohydrate-rich breakfast or no breakfast at all. The women’s sense of satiety, hormone levels and energy intake were measured at lunchtime. Their total daily energy intake was measured as well.

The participants also had to complete a cognitive concentration test during the study.

“We found that a protein-rich breakfast with skyr (a sour-milk product) and oats increased satiety and concentration in the participants, but it did not reduce the overall energy intake compared to skipping breakfast or eating a carbohydrate-rich breakfast,” says Mette Hansen, associate professor and PhD at the Department of Public Health, and one of the authors of the study.

Possible strategy to combat obesity?

The number of overweight people is increasing both in Denmark and across the globe. Obesity is often accompanied by lifestyle-related diseases such as type 2 diabetes.

Previous studies have shown that people who eat breakfast have a lower BMI than people who do not eat breakfast, and protein-rich foods have generally been shown to have an increased satiety effect compared to carbohydrate-rich and high-fat foods with the same calorie content.

The idea was therefore to test whether a protein-rich breakfast could be a good strategy to achieving greater satiety during the day and thus reducing daily calorie intake.

However, the solution is not that simple, says Mette Hansen:

“The results confirm that protein-rich meals increase a sense of satiety, which is positive with regard to preventing weight gain. However, the results also suggest that for this nutritional strategy to be effective, it’s not enough to just eat a protein-rich breakfast.”

Intriguing difference

The potential of replacing a carbohydrate-rich diet with a protein-rich diet can clearly be seen in the satiating effects measured in the study.

Several of the subjects had difficulty consuming the entire protein-rich breakfast consisting of skyr and oats.

“It’s intriguing that there can be such a big difference in the satiety effect of two different meals with the same calorie content. Had the women in the project been allowed to choose the size of the meal themselves, it’s likely that they’d have consumed more food and thereby more calories on the day

they were served bread and jam than on the day they were given skyr and oats,” explains Mette Hansen.

Further research needed

According to the researcher, although the study has provided important insights, it also has its limitations because only overweight young women participated in the study. The study is also based on relatively short-term observations, leaving open the question of how long-term dietary changes can affect health and weight.

Mette Hansen therefore points out that the study underlines the need for further research to understand how different types of food affect health over time.

“We already have new data incoming from a trial where participants received either a high-protein breakfast or a low-protein breakfast. The objective was to study how the different types of breakfast affect body composition and other parameters such as microbiota and cholesterol levels,” says Mette Hansen.

According to Mette Hansen, the results of these studies may result in the development of more targeted nutritional recommendations in the future.

Bariatric surgery may slow cognitive decline for people with obesity.

Cognition scores remained stable, while secondary executive function tests showed improvement
Cognition scores remained stable, while secondary executive function tests showed improvement

Within the next 10 years, it’s projected that up to 50% of United States adults will be affected by obesity, which is associated with cognitive impairment and dementia. 

Investigators at Michigan Medicine found that people with obesity who underwent bariatric surgery had stable cognition two years later

Researchers say it suggests that bariatric surgery may mitigate the natural history of cognitive decline expected in people with obesity.

The results are published in the Journal of Nutrition, Health & Aging.

“Since individuals with obesity experience more rapid cognitive decline than those without, stable cognition two years after bariatric surgery may be considered a success against historical trends, yet future controlled trials are needed to test this,” said first author Evan Reynolds, Ph.D., lead statistician for the NeuroNetwork for Emerging Therapies at Michigan Medicine.

Using a collection of memory and language tests developed by the National Institutes of Health, as well as the Rey Auditory Verbal Learning Test, the research team assessed over 85 bariatric surgery patients at two-year follow up.

They found that NIH Cognitive Battery test scores remained stable, with secondary executive function tests showing improvement. 

One of the memory assessments, however, declined following surgery.

While this current study is the largest to assess changes two years after bariatric surgery, researchers say, the results conflict with previous studies which found improved memory and executive functioning among similar patients.

“That study was primarily made up of patients who received gastric bypass, while our study was made up primarily of individuals that completed a sleeve gastrectomy,” Reynolds said. 

“To provide the best evidence on the effectiveness of bariatric surgery on cognition and potential differences between surgery types, we must conduct larger observational studies or randomized, controlled trials.”

After bariatric surgery, improvements in diabetes complications, such as peripheral neuropathy, chronic kidney disease and retinopathy, were not associated with improved cognition.

“Metabolic factors, including diabetes and obesity, are associated with cognitive decline, but we still need to better understand how best to treat these factors to improve patients’ cognitive outcomes,” said senior author Brian Callaghan, M.D.

Would taxing sugar-sweetened beverages improve population health and save money? Is this the “nudging society” gone too far?

Taxing sugar-sweetened beverages in Germany would improve population health and save money

A tiered tax system that incentivizes companies to reduce sugar content has greatest impact

Researchers model the taxation of sugar-sweetened beverages with population health and overall healthcare costs in Germany. CREDIT Leiada Krozjhen, Unsplash (CC0, https://creativecommons.org/publicdomain/zero/1.0/deed.en)

In Germany, taxing sugar-sweetened beverages could prevent or postpone cases of type 2 diabetes, extend healthy lifespans and save up to €16.0 billion in societal costs over the next 20 years, according to a new study led by Karl Emmert-Fees of the Technical University of Munich, published November 21st in the open access journal PLOS Medicine.

The World Health Organization has recommended that governments worldwide lessen the social and economic burden of cardiometabolic disease by taxing sugar-sweetened beverages. These taxes either reduce consumption by increasing the price, such as the one peso per liter tax in Mexico, or incentivize companies to reformulate their drinks with a lower sugar content, such as the tiered tax structure in the United Kingdom. Germany has not yet implemented a tax on sugar-sweetened beverages, so researchers estimated the health and economic impacts of these two possible taxation scenarios.

Through modeling, the researchers predicted the effects of a 20% tax on sugar-sweetened beverages and a tiered tax similar to the one used in the United Kingdom. For each scenario, they estimated changes in sugar consumption, weight, associated medical and societal costs, and the risk of type 2 diabetes, heart disease and stroke, from 2023 to 2043.

The researchers discovered that during the next 20 years, a tax on sugar-sweetened beverages could reduce sugar intake in the German adult population on average by 1 gram per day, prevent or postpone more than 132,000 cases of type 2 diabetes and save €9.6 billion by encouraging consumers to change their behavior. A tiered structure, however, would reduce sugar consumption on average by 2.34 grams per day, prevent or postpone more than 244,000 cases of type 2 diabetes and save €16.0 billion by incentivizing companies to sell drinks with less sugar.

While both tax systems would help reduce the health burden and societal costs of cardiometabolic disease, the researchers conclude that a tiered tax would likely have the largest impact. The researchers conclude that taxing sugar-sweetened beverages would be a viable policy option for German decision makers that would improve the health of the German population.

Emmert-Fees adds, “Overall, we found that the taxation of sugar-sweetened beverages could have a substantial impact on population health in Germany. Particularly people who consume a lot of these beverages would benefit from the highest reduction in sugar intake.”

Research shows obesity is associated with worse flare symptoms and quality of life in people with early rheumatoid arthritis

Obesity
Obesity

A recent study from Hospital for Special Surgery (HSS) and others has found a correlation between obesity and more severe disease flare symptoms that negatively affect quality of life in patients with early rheumatoid arthritis (RA), a systemic, autoimmune, inflammatory disorder affecting multiple joints in the body. The study will be presented at ACR Convergence 2023, the annual meeting of the American College of Rheumatology.

RA is usually treated with a combination of medications to relieve swelling and pain while regulating the immune system. Joint surgery to relieve pain and disability, including joint replacement, may also be considered when these nonsurgical methods fail to provide lasting benefit.

“If a person with RA is experiencing frequent flares, weight could be a contributing factor,” said study principal investigator Vivian P. Bykerk, BSc, MD, FRCPC, a rheumatologist at HSS. “It may be helpful for patients to talk with their doctor about how to lose weight.”

To conduct their research, investigators used data from the prospective RA registry study called the Consortium of Early ArThritis CoHorts-USA Study (CATCH-US). This study, conducted at HSS and Johns Hopkins School of Medicine, recruited participants with at least two swollen joints and early or recent onset rheumatoid arthritis (symptoms ≤12/≤24 months) between December 2014 and May 2023. The researchers collected baseline characteristics and patient reported outcomes at each visit.

In this study, flares were determined using the OMERACT RA-Flare Questionnaire (RA-FQ), a patient-reported outcomes tool that assesses symptoms of pain, stiffness, fatigue, impacts on physical function, and impacts on social participation. Items in this tool are scored from 0 to 10, with 0 being best and 10 worst. All five scores are summed for an overall score range of 0 to 50. Investigators also collected an Evaluator Global Assessment (EGA) score, indicating rheumatoid arthritis clinical disease activity; this was scored by the enrolling rheumatologist between 0 (not active) and 10 (very active). Using a multivariable linear regression model, the investigators tested the correlation between body mass index (BMI) and RA-FQ scores, considering EGA scores and demographic factors such as age, sex, and ethnicity as covariates.

There were 134 participants in the study; 85% were female, 71% were white, and 87% were non-Hispanic. Almost half (46%) were overweight or obese. The median age was 47.3 years, and the median BMI was 24.3.

“Our key finding was that there was a linear relationship between having a higher BMI and having a higher RA-FQ score,” said lead study author Margaret Butler, a research assistant in the Department of Medicine at HSS. “As BMI got higher, RA-FQ scores increased as well, indicating that the patient would have poorer outcomes. Having a higher BMI also predicted worse scores in each of the five individual categories except physical function. The relationship was even more pronounced when you separated patients by healthy BMI, overweight BMI, and obese BMI, with patients having an obese BMI having worse RA-FQ scores compared to the other two groups.”

The researchers say that clinicians should consider patients’ BMI and RA-FQ scores when formulating treatment plans for RA flares. “Doctors should encourage patients to lose weight, if determined to be the root cause of frequent flare ups to avoid prescribing additional medications to control symptoms,” said Dr. Bykerk. “Losing weight for people with RA is a difficult problem because they have lost significant muscle mass, and that is our metabolic-driving tissue. To lose weight, patients have to build muscle and have a more nourishing, high-protein diet. We need programs to help patients do this.”

A previous study by the researchers revealed that fewer patients with RA go into remission if they are obese or overweight. Future studies will examine whether BMI influences RA flares throughout the course of the disease.

Obesity is linked to neurodegeneration through insulin resistance.

Obesity linked to neurodegeneration through insulin resistance

Sugar fly. Artistic rendering generated by DALL.E the prompt used is “The drawing of the fruit fly Drosophila in a dark background in the style of Seurat”. The researchers fed fruit flies high sugar diets and examined the effect on brain function. CREDIT Akhila Rajan created this image using DALL-E and owns it. They are making it available under CC-BY 4.0 (CC-BY 4.0, https://creativecommons.org/licenses/by/4.0/)

Researchers led by Mroj Alassaf at the Fred Hutchinson Cancer Research Center in the United States have discovered a link between obesity and neurodegenerative disorders like Alzheimer’s disease. Using the common fruit fly, the research shows that a high-sugar diet — a hallmark of obesity — causes insulin resistance in the brain, which in turn reduces the ability to remove neuronal debris, thus increasing the risk of neurodegeneration. Publishing November 7th in the open access journal PLOS Biology, the research will impact therapies designed to reduce the risk of developing neurodegenerative diseases.

Although obesity is known to be a risk factor for neurodegenerative disorders like Alzheimer’s disease and Parkinson’s disease, exactly how one leads to the other remains a mystery. The new study focused on answering this question by taking advantage of the similarity between humans and fruit flies. Having previously shown that a high-sugar diet leads to insulin resistance in the peripheral organs of flies, the researchers now turned to their brains. Specifically, they examined glial cells because microglial dysfunction is known to lead to neural degeneration.

Levels of the protein PI3k indicate how much a cell is able to respond to insulin. The researchers found that the high sugar diet led to reduced PI3k levels in glial cells, indicating insulin resistance. They also looked at the fly equivalent of microglia, called ensheathing glia, whose primary function is to remove neural debris, such as degenerating axons. They observed that these glia had low levels of the protein Draper, indicating impaired function. Further tests revealed that artificial reduction of PI3k levels led to both insulin resistance and low Draper levels in ensheathing glia. Finally, they showed that after actually damaging olfactory neurons, the ensheathing glia could not remove the degenerating axons in the flies on the high sugar diet because their Draper levels did not increase.

The authors add, “Using fruit flies, the authors establish that high-sugar diets trigger insulin resistance in glia, disrupting their ability to clear neuronal debris. This study provides insight into how obesity-inducing diets potentially contribute to the increased risk of neurodegenerative disorders.”