More than two million nights of sleep and blood pressure were examined by the researchers.

Inconsistencies in sleep time and length were linked to a higher risk of hypertension, according to a study that examined more than two million nights of sleep and blood pressure data.

According to the findings, a 9% to 15% higher risk of hypertension was linked to high sleep duration irregularity. Furthermore, a 38-minute increase in sleep midpoint irregularity was linked with an 11% risk increase, while a 31-minute increase in sleep start time irregularity was associated with a 29% risk increase.

“This new approach to noninvasive nightly monitoring of sleep duration and timing in people’s homes for an average period of six months each combined with regular blood pressure monitoring has shown us just how important having a regular sleep routine and getting enough sleep is for your health, in this case, your heart health,” said lead author Hannah Scott, who has a doctorate in sleep health and is a sleep health research associate at the Adelaide Institute for Sleep Health (AISH), Flinders University.

“These novel data shed new light on the restorative benefits of sleep and raise potential concerns for the substantial proportion of shift workers in our modern 24-hour society.”

12,300 volunteers aged 18 to 90 provided data during a nine-month period, which the researchers then analyzed. A portable blood pressure monitor and an under-mattress sleep device were used to capture the metrics. The standard deviation of total sleep time was used to determine the regularity of the sleep duration. Similarly, the standard deviation in sleep onset time and sleep midpoint was used to determine the regularity of sleep timing.

Logistic regressions controlling for age, sex, body mass index, and average total sleep time were conducted to investigate potential associations between sleep regularity and hypertension, which was found in 2,499 participants.

“These new insights into the potential adverse impact of irregular sleep timing and duration on heart health further highlight the importance of the role synchronizing the body clock and prioritizing enough sleep opportunity for optimal health and wellbeing,” said senior author Danny Eckert, who has a doctorate in sleep and respiratory physiology and is professor and director of AISH.

The researchers noted that prior studies of sleep and heart health have been limited in sample size and restricted to a short period of time. The current study investigated associations between sleep regularity and hypertension in a large, global sample over multiple months.

Reference: “0204 Sleep Irregularity Is Associated with Increased Risk of Hypertension: Data From Over Two Million Nights” by Hannah Scott, Bastien Lechat, Amy Reynolds, Nicole Lovato, Pierre Escourrou, Peter Catcheside and Danny Eckert, 25 May 2022, SLEEP.
DOI: 10.1093/sleep/zsac079.202

This was an unfunded investigator-initiated study. Deidentified data were provided by Withings for unrestricted investigator-led analysis. One of the co-authors serves as a consultant for Withings.

New 3D model shows that megalodon could eat prey the size of entire killer whales. Credit: J. J. Giraldo

Megalodon, the largest shark that ever lived, is famous for its gigantic, human-hand-sized teeth. However, there is little fossil evidence of its whole body. International researchers in collaboration with the University of Zurich used an exceptionally preserved specimen to create a 3D computer model of its full body. According to their results, the megalodon could fully consume prey the size of today’s killer whales and then roam the seas without more food for two months.

The reconstructed megadolon (Otodus megalodon) was 16 meters (52 feet) long and weighed over 61 tons. It was estimated that it could swim at around 1.4 meters per second (3.1 mph), required over 98,000 kilo calories every day, and had a stomach volume of almost 10,000 liters. These results suggest that the megalodon could travel long distances and was capable of eating whole prey up to 8 meters (26 feet) long. Notably, this is the size of modern killer whales, today’s top ocean predator. An ability to eat large apex predators of comparable size millions of years ago places megalodon at a higher trophic level than modern top predators.

The reconstructed megadolon (Otodus megalodon) was 16 meters long and weighed over 61 tons. It was estimated that it could swim at around 1.4 meters per second. Credit: J. J. Giraldo

Well-preserved spine enables reconstruction

These are the findings of an international study carried out in collaboration with the University of Zurich and published on August 17 in Science Advances. The research was only possible due to the 3D modeling of one individual megalodon which was discovered in the 1860s. Against all odds, a sizeable portion of its vertebral column was left behind in the fossil record after the creature died in the Miocene oceans of Belgium about 18 million years ago. It is estimated that it was 46 years old when it died.

“Shark teeth are common fossils because of their hard composition which allows them to remain well preserved,” says first author Jack Cooper, PhD student at Swansea University. “However, their skeletons are made of cartilage, so they rarely fossilize. The megalodon vertebral column from the Royal Belgian Institute of Natural Sciences is, therefore, a one-of-a-kind fossil.”

From single vertebra to whole body mass

The research team, which includes researchers from Switzerland, the UK, the United States, Australia, and South Africa, first measured and scanned every single vertebra, before reconstructing the entire column. Next, they attached the column to a 3D scan of a megalodon’s dentition from the United States. Finally, they completed the model by adding “flesh” around the skeleton using a 3D scan of the body of a great white shark from South Africa.

“Weight is one of the most important traits of any animal. For extinct animals we can estimate the body mass with modern 3D digital modeling methods and then establish the relationship between mass and other biological properties such as speed and energy usage,” says co-author John Hutchinson, professor at the Royal Veterinary College in the UK.

A trans-oceanic super-apex predator

The high energetic demand would have been met by feeding on the calorie-rich blubber of whales, in which megalodon bite marks have previously been found in the fossil record. An optimal foraging model of potential megalodon prey encounters found that eating a single 8-meter-long (26-foot-long) whale may have allowed the shark to swim thousands of miles across oceans without eating again for two months.

“These results suggest that this giant shark was a trans-oceanic super-apex predator,” says Catalina Pimiento, Professor at the University of Zurich and senior author of the study. “The extinction of this iconic giant shark likely impacted global nutrient transport and released large cetaceans from a strong predatory pressure.”


The complete 3D model can now be used as a basis for future reconstructions and further research. The novel biological inferences drawn from this research represent a leap in our knowledge of this singular super predator. The study helps to better understand the ecological function that megafaunal species play in marine ecosystems and the large-scale consequences of their extinction.

Reference: “The extinct shark Otodus megalodon was a transoceanic superpredator: Inferences from 3D modeling” by Jack A. Cooper, John R. Hutchinson, David C. Bernvi, Geremy Cliff, Rory P. Wilson, Matt L. Dicken, Jan Menzel, Stephen Wroe, Jeanette Pirlo and Catalina Pimiento, 17 August 2022, Science Advances.
DOI: 10.1126/sciadv.abm9424

According to the researchers, following a vegan diet improves your diet quality leading to weight loss.

Researchers find that a vegan diet high in legumes helps people lose weight.

According to recent research from the Physicians Committee for Responsible Medicine that was published in the Journal of the Academy of Nutrition and Dietetics, a vegan diet enhances diet quality, which results in lower weight and enhanced insulin sensitivity. Increased consumption of legumes and reduced intake of meat, fish, and poultry were the two factors most strongly related to weight loss.

“Our research shows that the best way to improve the quality of your health is to improve the quality of the foods you eat,” says Hana Kahleova, MD, Ph.D., director of clinical research at the Physicians Committee and a study co-author. “That means avoiding animal products and eating a vegan diet rich in fruits, vegetables, grains, and beans.”


244 overweight people who participated in the 16-week trial were split into two groups at random: those who made no dietary modifications and those who followed a low-fat vegan diet consisting of vegetables, grains, legumes, and fruits without calorie limitations. Weight, body fat mass, insulin sensitivity, and diet quality were all monitored by researchers. 219 people who finished the whole study and sent in their final diet records were included in the final data analysis.

Participants on the vegan diet lost an average of 13 pounds and 9.1 pounds of fat mass. Body weight and fat mass did not decrease in the group that made no diet changes. In the vegan group, increases in fruit, legume, meat alternative, and whole grain intake and decreases in animal products, added oils, and animal fats were associated with weight loss:

• Fruit: Increased intake of whole fruit was associated with a decrease in body weight.
• Legumes and Meat Alternatives: Increased legume consumption was associated with decreased weight, fat mass, and visceral adipose tissue. Consuming more meat alternatives, including tofu, tempeh, and veggie burgers, was associated with a decrease in body weight.
• Grains: Increased consumption of whole grains was associated with decreased body weight and fat mass.
• Eggs and Dairy Products: Decreased egg intake was correlated with decreased weight. Decreased high-fat dairy intake was associated with decreased weight and fat mass.
• Meat, Fish, and Poultry: Reductions in the combined intake of total meat, fish, and poultry were associated with weight loss and a decrease in fat mass.
• Added Fats: Decreases in intake of added animal fats were associated with decreases in weight and fat mass. Decreased intake of added oils also correlated with decreases in weight and fat mass.

The vegan group also experienced improvements in insulin sensitivity.


The vegan group’s diet quality, measured by the Alternative Healthy Eating Index-2010 (AHEI) score, also increased by 6 points on average in contrast to no significant change in the group that did not make a diet change. The AHEI was developed by researchers at the Harvard School of Public Health to identify dietary patterns associated with a lower risk of chronic disease. The index is comprised of foods to eat more often, such as fruits and vegetables, and those to eat less often, such as red and processed meat. The higher the AHEI score, the lower the risk for chronic disease.

Reference: “Changes in Food and Nutrient Intake and Diet Quality on a Low-Fat Vegan Diet Are Associated with Changes in Body Weight, Body Composition, and Insulin Sensitivity in Overweight Adults: A Randomized Clinical Trial” by Lelia Crosby, BA, RD, LD, Emilie Rembert, BS, Susan Levin, MS, RD, CSSD, Amber Green, BS, RD, LD, Zeeshan Ali, Ph.D., Meghan Jardine, MS, MBA, RDN, LD, CDE, Minh Nguyen, MS, RD, Patrick Elliott, BS, Daniel Goldstein, BA, Amber Freeman, Meka Bradshaw, Danielle N. Holtz, Richard Holubkov, Ph.D., Neal D. Barnard, MD and Hana Kahleova, MD, Ph.D., 19 April 2022, Journal of the Academy of Nutrition and Dietetics.
DOI: 10.1016/j.jand.2022.04.008

The scientists also found that the deterioration that develops within the joint might be slowed down by walking as exercise.

How walking can lead to healthier knees.

According to a recent study published in Arthritis & Rheumatology and conducted by Baylor College of Medicine researchers, walking may help people age 50 and older who have knee osteoarthritis, the most prevalent kind of arthritis, reduce frequent pain. Additionally, the study’s results suggest that walking for exercise might be a successful treatment for reducing joint deterioration.

“Until this finding, there has been a lack of credible treatments that provide benefit for both limiting damage and pain in osteoarthritis,” said Dr. Grace Hsiao-Wei Lo, assistant professor of immunology, allergy, and rheumatology at Baylor, chief of rheumatology at the Michael E. DeBakey VA Medical Center and first author of the paper.


The participants in the Osteoarthritis Initiative, a multiyear observational study in which they self-reported how often and for how long they walked for exercise, provided the data for the study. Participants who reported 10 or more occurrences of exercise starting at the age of 50 or later were categorized as “walkers,” whereas those who reported fewer instances were categorized as “non-walkers.”

Those who reported walking for exercise had 40% decreased odds of new frequent knee pain compared to non-walkers.

“These findings are particularly useful for people who have radiographic evidence of osteoarthritis but don’t have pain every day in their knees,” said Lo, who also is an investigator at the Center for Innovations in Quality, Effectiveness, and Safety at Baylor and the VA. “This study supports the possibility that walking for exercise can help to prevent the onset of daily knee pain. It might also slow down the worsening of damage inside the joint from osteoarthritis.”


Lo noted that additional health advantages of walking for exercise include improved cardiovascular health, a lower risk of obesity, diabetes, and some cancers, which are the main justifications for the Centers for Disease Control’s physical activity recommendations, first published in 2008 and updated in 2018. Contrary to medications, which sometimes have a hefty price tag and the chance of side effects, walking for exercise is a free activity with few side effects.

“People diagnosed with knee osteoarthritis should walk for exercise, particularly if they do not have daily knee pain,” advises Lo. “If you already have daily knee pain, there still might be a benefit, especially if you have the kind of arthritis where your knees are bow-legged.”

Reference: “Association Between Walking for Exercise and Symptomatic and Structural Progression in Individuals with Knee Osteoarthritis: Data from the Osteoarthritis Initiative Cohort” by Grace H. Lo, MD, MSc, Surabhi Vinod, MD, Michael J. Richard, BS, Matthew S. Harkey, Ph.D., Timothy E. McAlindon, MD, Andrea M. Kriska, Ph.D., Bonny Rockette-Wagner, Ph.D., Charles B. Eaton, MD, Marc C. Hochberg, MD, Rebecca D. Jackson, MD, C. Kent Kwoh, MD, Michael C. Nevitt, Ph.D. and Jeffrey B. Driban, Ph.D., 8 June 2022, Arthritis & Rheumatology.
DOI: 10.1002/art.42241

Lo was supported by K23 AR062127, an NIH/NIAMS-funded mentored award; this work was supported in part by resources at the VA HSR&D Center for Innovations in Quality, Effectiveness, and Safety (#CIN 13-413), at the Michael E. DeBakey VA Medical Center.