Tag: 11/2/21

Plant-based Protein Increases Bone Turnover

A Finnish study has found that increasing the share of dietary protein from plant versus animal sources leads to increased bone turnover and possible fracture risk.

The 136 adult participants followed one of three diets for a period of three weeks. One of them was modelled on the typical Finnish diet where 70% of protein came from animal sources and the rest from cereals. The second had half the protein come from animal sources and the other half from plants, and the third had 70% of protein from plants and the rest from animal sources

Dairy milk, which is fortified with vitamin D in Finland, was substituted with unfortified plant-based milk, which may have been a confounding variable. There was a marked increase in bone formation and resorption markers, which in the long term could indicate bone loss. These findings are in line with the Oxford-EPIC study, which followed participants for 18 years and found a higher rate of fractures in vegetarians compared to those on an omnivorous diet.

“The results could be different if fluid dairy products had been replaced with plant-based drinks fortified with vitamin D and calcium,” said Docent Suvi Itkonen, Department of Food and Nutrition, Faculty of Agriculture and Forestry, University of Helsinki. “Then again, the average vitamin D intake was also below the recommended level in the group where subjects consumed the animal protein-rich diet, but not to the same extent as in the other groups.”

Source: News-Medical.Net

Journal information: Itkonen, S. T., et al. (2021) Partial Replacement of Animal Proteins with Plant Proteins for 12 Weeks Accelerates Bone Turnover Among Healthy Adults: A Randomized Clinical Trial. The Journal of Nutrition.doi.org/10.1093/jn/nxaa264.

African Genetic Data Needed to Complete the DNA Picture

A $4.5 billion initiative to gather genomic data from African populations has been put forward to help fill the gaps in understanding the human genome.

Genome Wide Assay Studies (GWAS) have yielded a huge amount of insight into genetic associations with disease and roles in bodily function, transforming medicine. But the picture is still incomplete, and there are large gaps remaining.

While the genomes of Europeans and Americans has been well mapped, the genomes of Africans remain virtually a blank state despite having far more genetic diversity than any other region. Genome mapping has come a long way in the two decades since the first genome was sequenced, falling in cost from $3 billion to around $1000.

“Most genomic research on the African continent over the last two decades has largely been driven by agendas defined more by European and American investigators,” Ambroise Wonkam, a medical genetics professor and deputy dean of research at the University of Cape Town’s Faculty of Health Sciences, told AFP.

“The Three Million African Genomes (3MAG) project would require sequencing individuals carefully selected across Africa to cover ethnolinguistic, regional and other groups,” Prof Wonkam said. A similar study to map the genomes of 100 000 Asian people is underway. 

The continent’s enormous genetic diversity no doubt holds a great number of surprises and important discoveries. Making his case in a comment in Nature, Prof Wonkam said that having access to such a diverse database would make it much easier to track down mutations.

“The aim is to capture the full scope of Africa’s genetic variation—for the benefit of all human populations and to ensure equitable access to genetic medicine.”

For example, a variant of the PCSK9 gene that is correlated with dyslipidaemia only came to light because it was 200 times more common in African Americans than Europeans.

Citing another example, Prof Wonkam said, “The inclusions of even a small number of black Americans in control cohorts probably would have prevented the misclassification of benign variants as causing cardiomyopathy.”

The relatively few GWAS of African populations that have been done also revealed a genetic susceptibility to type-2 diabetes that had previously gone unreported, and up to half of African populations have a gene variant associated with severe side effects to the HIV drug efavirenz.

When the genomes of 910 people of African descent were sequenced, it revealed large gaps in the ‘reference genome’ used by researchers around the world, Jesse Gillis, a researcher at the Stanley Institute for Cognitive Genomics in New York, noted in a study in BMC.

“Approximately 10 percent of DNA sequences—some 300 million base pairs—from these genomes were ‘missing’,” he stated.

Prof Wonkam has said that the study should mostly be funded by African governments, but international organisations should help foot the bill too. 

Source: Medical Xpress

Journal information: Comment: Sequence three million genomes across Africa, Nature (2021). DOI: 10.1038/d41586-021-00313-7 , www.nature.com/articles/d41586-021-00313-7

Study Reveals the Genetics of Daytime Napping

Genes play a role in how often, if at all, people take daytime naps, research has revealed.

Identifying dozens of genetic regions associated with napping, a team of researchers from Massachusetts General Hospital (MGH) and the University of Murcia in Spain conducted the largest study of its kind. Additionally, they discovered genetic links to cardiometabolic health. 

“Napping is somewhat controversial,” said Hassan Saeed Dashti, PhD, RD, of the MGH Center for Genomic Medicine, co-lead author of the report. Dashti noted that some countries (such as Spain) which featured daytime napping in their culture now discourage it. Conversely, some companies in the United States now promote napping as a productivity. “It was important to try to disentangle the biological pathways that contribute to why we nap,” said Dashti.

In a Genome-Wide Association Study, the MGH researchers used genomic data obtained from the UK Biobank, which holds the genomes of 452 633 people. They replicated their findings using data from the company 23andMe which has obtained data from 541 333 people. The participants had rated their daytime napping habits, and a subset wore accelerometers to provide objective verification of resting behaviour. A number of the genes analysed were also already known to be associated with sleep.

The GWAS identified 123 genetic areas associated with napping. On further investigation, the researchers identified three factors which promote napping:

Sleep propensity: Some people require more sleep than others.
Disrupted sleep: Daytime napping can make up for poor sleep the previous night.
Early morning awakening: People who wake up too early can ‘get back’ some sleeping` time.

“This tells us that daytime napping is biologically driven and not just an environmental or behavioural choice,” said Dashti. Some of these subtypes were linked to cardiometabolic health concerns, such as waist circumference.

“Future work may help to develop personalised recommendations for siesta,” concluded Garaulet.

A number of the genes related to napping were already associated with orexin, a neuropeptide involved in wakefulness, as well as a number of other areas such as mood and feeding behaviour. This pathway is known to be associated with narcolepsy, but the findings suggested that smaller perturbations seem to be associated with napping.

Source: Medical Xpress

Journal information: Dashti, H.S., Daghlas, I., Lane, J.M. et al. Genetic determinants of daytime napping and effects on cardiometabolic health. Nat Commun 12, 900 (2021). doi.org/10.1038/s41467-020-20585-3 , www.nature.com/articles/s41467-020-20585-3

Opioid Overdoses in US Increasing due to COVID

The COVID pandemic has not seen a drop in the United States’ opioid crisis, rather there has been an exacerbation of the problem.

A study published in JAMA Psychiatry examined the impact that the COVID pandemic had on the US opioid crisis. 

Opioid misuse and addiction is an ongoing and increasing problem in the US, making up two thirds of overdoses. Some three million Americans have suffered opioid use disorder at some point. With approximately 100 million Americans living with chronic or acute pain, the situation is seemingly intractable. In 2019, there were 70 000 deaths from opioid overdoses, making it a top priority in public health, academic, and political debates. When the COVID pandemic hit, it did not displace the opioid crisis through distraction or somehow preventing access to opioids, it fanned the flames of it. 

Researchers analysed 190 million ED visits, and over March to October 2020. they observed an increase of  up to 45% in weekly opioid overdose admissions over the same period in 2019. Overall, ED visits for opioid overdoses had increased 28.8% compared to the previous year.

In September, the CDC warned that deaths from opioid overdoses were up by 38.4% in the first half of the year. The many stresses of the pandemic, such as its associated lockdowns and job losses and losing loved ones, has fuelled the opioid abuse. The same study also found that visits to the ED for mental health conditions, domestic violence, and child abuse and neglect increased over the same period of time, along with suicide attempts. 

Source: ABC News

Journal information: Holland KM, Jones C, Vivolo-Kantor AM, et al. Trends in US Emergency Department Visits for Mental Health, Overdose, and Violence Outcomes Before and During the COVID-19 Pandemic. JAMA Psychiatry. Published online February 03, 2021. doi:10.1001/jamapsychiatry.2020.4402

Decreasing Cancer Deaths with Population-wide Vitamin D

Supplementation Scientists have estimated that supplementing the over-50 population in Germany with sufficient vitamin D would save 30 000 lives which would otherwise be lost to cancer, gaining some 300 000 extra years of life, all while reducing healthcare costs.

Vitamin D is created in the body through the interaction of UV-B radiation with dehydrocholesterol, which is produced in the skin, into vitamin D3 (cholecalciferol). In many countries, populations have chronically low vitamin D levels due to more time being spent indoors. Vitamin D supplementation is associated with the prevention and treatment of nutritional rickets and osteomalacia, but it is important for other aspects of health such as prevention of respiratory tract infections and asthma. In countries such as Germany, low sunlight levels for much of the year combined with more time spent indoors results in much of the population having inadequate vitamin D levels. 

Three large meta-analyses had indicated that mortality due to cancer is reduced by 13% with vitamin D supplementation.

“In many countries around the world, the age-adjusted rate of cancer mortality has fortunately declined over the past decade,” said Hermann Brenner, epidemiologist at the German Cancer Research Centre (DKFZ).  However, given the often considerable costs of many new cancer drugs, this success has often come at a high price. Vitamin D, on the other hand, is comparatively inexpensive in the usual daily doses.”

To get their figures, the scientists used a daily administration of 1000 international units of vitamin D, costing 25 Euros per person per year. Since about 36 million people over the age of 50 live in Germany, this results in an annual cost of 900 million Euros.

The researchers calculated the number of years lost to cancer death, and also did not account for testing of vitamin D levels, as the proposed 1000 international units were far short of an overdose danger. The study estimated that if the entire German population over the age 50 were given sufficient supplements to achieve the recommended levels of vitamin D, 30 000 cancers deaths annually would be prevented.

“In view of the potentially significant positive effects on cancer mortality – additionally combined with a possible cost-saving – we should look for new ways to reduce the widespread vitamin D deficiency in the elderly population in Germany. In some countries, foods have even been enriched with vitamin D for many years – for example, in Finland, where cancer mortality rates are about 20 percent lower than in Germany. Not to mention that there is mounting evidence of other positive health effects of adequate vitamin D supply, such as in lung disease mortality rates,” said Brenner, adding, “Finally, we consider vitamin D supplementation so safe that we even recommend it for newborn babies to develop healthy bones.”

Spending about 12 minutes two to three times a week in the sun, with face, hands and parts of the arms and legs all uncovered and without sunscreen is sufficient to provide enough vitamin D.

Source: News-Medical.Net

Journal information: Niedermaier, T., et al. (2021) Vitamin D supplementation to the older adult population in Germany has the cost‐saving potential of preventing almost 30,000 cancer deaths per year. Molecular Oncology. doi.org/10.1002/1878-0261.12924.

Appetite Control With Semaglutide is a ‘Game Changer’ for Obesity

Semaglutide, a drug normally used to treat type 2 diabetes promises to make a huge impact in the fight against obesity and the diseases associated with it.

A 15 month study involving over 2000 participants resulted in an average weight loss of 15kg for those taking the appetite suppressing drug.   
Speaking to the BBC, Jan, one of the participants in the trial, lost 28kg, which was over a fifth of her body weight. “The drug changed my life and completely altered my approach to food,” she said.

She said dieting had made her “miserable” but taking the drug was completely different as she was less hungry. 

However, that the trial has ended for Jan, her appetite has returned to normal and she is gaining weight. She said: “It felt effortless losing weight while on the trial, but now it has gone back to feeling like a constant battle with food.”

Recently approved by the FDA and European Medicines Agency, semaglutide is normally used to treat type 2 diabetes as an adjunct to diet and exercise, but the trial sought to establish its use in higher doses as an appetite suppressant. One group was given a weekly semaglutide injection while the other received a placebo, and dietary and lifestyle guidance was given to both groups with the aim of losing weight. 
The drug mimics GLP-1, a hormone that is released after a meal. The trial participants receiving semaglutide lost an average of 15kg compared to 2.6kg for  placebo, with 32% of participants receiving semaglutide losing a fifth of their body weight compared to 2% for placebo.

Side effects included nausea, diarrhoea, vomiting and constipation.
Prof Sir Stephen O’Rahilly, from the University of Cambridge, said: “The amount of weight loss achieved is greater than that seen with any licensed anti-obesity drug.

“This is the start of a new era for obesity drug development with the future direction being to achieve levels of weight loss comparable to semaglutide, while having fewer side-effects.”

Dr Duane Mellor, a dietician and from Aston Medical School, said: “It is useful to have a potential option to help people lose weight, however we need to acknowledge that weight loss will still need lifestyle change, and that any medication or change in lifestyle can bring potential risks and side-effects.

“So, it is always wise to speak to a health professional before trying to lose weight.”

Source: BBC News