Latest News & Research: 13 August 2019

This week: Harmful effects of weight stigma in men • Snacks better than meals for nightwork energy levels • Whole-body vibration may lower inflammation

Harmful effects of weight stigma in men

Weight stigma is compromising the health of men in many of the same ways it does women, according to the latest research from the Rudd Center for Food Policy and Obesity at the University of Connecticut.

The new study of nearly 2,000 men found those who experienced weight stigma had increased odds of engaging in binge eating and had lower self-rated health.

While a significant percentage of men – as much as 40% – say they have experienced weight stigma, they have received far less attention in research than women. But, weight stigma is pervasive against people with obesity, and can contribute to both physical and emotional health problems for those who experience it.

‘It’s often assumed that conversations about weight loss, poor body image, and dieting are more salient for women’ said Mary Himmelstein, postdoctoral fellow and lead author of the study; ‘Men are frequently overlooked, but that does not necessarily mean that men are less affected by weight stigma or less likely to internalise negative biases.’

The study, published in the journal Obesity, involved two groups of men: 1,249 men from a diverse national survey panel, and 504 men from an online data collection service. Both groups completed identical surveys about their experiences of weight-based stigma, how much they internalised these experiences (e.g. blamed themselves), as well as their psychological wellbeing and health behaviours.
Researchers found that both experienced and internalised weight stigma were associated with more depressive symptoms and more dieting behaviours in men.

These findings suggest the need for increased attention to men not only in research on links between weight stigma and health, but also among health professionals treating men for various health conditions, in which weight stigma may play a contributing role, said Himmelstein.

In particular, it may be useful for health care providers to ask men about weight stigma to help identify those who may be vulnerable to depression or disordered eating behaviors, which are underdiagnosed in men, she added.

‘Weight stigma is not a gendered issue. It can affect men’s health in the same damaging ways in which we already know that it harms women’s health, and neglecting these issues in men, either in research or clinical practice, may put them at a serious disadvantage in treatment’ said Himmelstein; ‘Opportunities for supportive interventions should be available for men, women, and non-binary individuals alike to help them cope with weight stigma in less harmful ways.’

Source: University of Connecticut


Snacks better than meals for nightwork energy levels

If you or your clients are among Australia’s 1.4 million shiftworkers, eating at irregular times is just par for the course – but have you ever stopped to think about the impact this might have on the body?

In a new research study by the University of South Australia, researchers have investigated whether altering food intake during the nightshift could optimise how shiftworkers feel during the night and reduce their sleepiness.

Testing the impact of either a snack, a meal, or no food at all, the study found that a simple snack was the best choice for maximising alertness and productivity.

Lead researcher and UniSA PhD candidate Charlotte Gupta says the finding has the potential to help thousands of shiftworkers who work during the night.

‘In today’s 24/7 economy, working the nightshift is increasingly common, with many industries – health care, aviation, transport and mining – requiring employees to work around the clock’ Gupta said; ‘As a nightshift worker, finding ways to manage your alertness when your body is naturally primed for sleep can be really challenging. We know that many nightshift workers eat on-shift to help them stay awake, but until now, no research has shown whether this is good or bad for their health and performance. This is the first study to investigate how workers feel and perform after eating different amounts of food. The findings will inform the most strategic eating patterns on-shift and can hopefully contribute to more alert and better performing workers.’

In Australia, of the 1.4 million shiftworkers, 15% (or over 200,000) regularly work a night or evening shift. Working at night-time conflicts with a person’s internal circadian clock, making it harder to stay focused and awake. Managing fatigue is therefore critical for workplace health and safety.

Over a 7-day simulated shiftwork protocol, the study assessed the impact of three eating conditions (a meal comprising 30% of energy intake over a 24-hour period (for example, a sandwich, muesli bar, and apple); a snack comprising 10% of energy intake (for example, just the muesli bar and apple); and no food intake at all) each consumed at 12:30am. The 44 participants were randomly split into the three test-conditions and were asked to report on their levels of hunger, gut reaction and sleepiness.

The results showed that while all participants reported increased sleepiness and fatigue, and decreased vigour across the nightshift, consuming a snack reduces the impact of these feelings more so than a meal or no food at all. The snack group also reported having no uncomfortable feelings of fullness as noted by the meal group.

Gupta says the next step in the research is to investigate the different types of snacks and how they affect shiftworkers differently.

‘Now that we know that consuming a snack on nightshift will optimise your alertness and performance without any adverse effects, we’re keen to delve more into the types of snacks shiftworkers are eating’ Gupta said; ‘Lots of shiftworkers snack multiple times over a nightshift, and understanding the different macronutrient balances is important, especially as many report consuming foods high in fat, such as chips, chocolate and fast foods. We’re keen to assess how people feel and perform after a healthy snack versus a less-healthy, but potentially more satisfying snack like chocolate or lollies. Ultimately, the goal is to help Australian shiftworkers on the nightshift to stay alert, be safe, and feel healthy.’

Source: University of South Australia


Whole-body vibration may lower inflammation

A new study in mice has revealed the potentially beneficial effects of whole-body vibration (WBV) training on inflammation and the microbiome.

Requiring a person to stand on a platform that typically vibrates at a frequency of 15–70 hertz (Hz) and an amplitude of 1–10 millimeters (mm), WBV gained popularity as an exercise tool in the 2000’s.

The human body automatically adapts to ‘repeated, rapid, and short intermittent exposure to oscillations’ from this type of vibrating platform, which prompted researchers to classify WBV as a ‘light neuromuscular resistance training method.’

Research into the practice has brought to light various health benefits. Some studies have shown that WBV improves muscle performance, bone density, strength, and balance, as well as helping to reduce body fat in the long term.

Previous research has also shown that WBV can reduce inflammation and even ‘reverse many symptoms’ of type 2 diabetes, such as frequent urination and excessive thirst. Research indicates that it also improves blood sugar control and insulin resistance.

For the new study, however, researchers from the Medical College of Georgia (MCG) and the Dental College of Georgia (DCG), at Augusta University, set out to investigate how WBV might exert these benefits on metabolic health.

Dr Jack Yu, head of pediatric plastic surgery at MCG, is one of the corresponding authors of the study, which appears in theInternational Journal of Molecular Sciences, together with Dr Babak Baban, immunologist and interim associate dean for research at DCG.

Yu and Baban used a standard mouse model of type 2 diabetes. This involves using mice that have been genetically engineered to have a leptin deficiency, which puts them at risk of obesity, insulin resistance, and diabetes.

For the experiments aimed at examining macrophages (immune cells with a key role in inflammation and gut health) the researchers used two groups of male mice; six mice received the intervention and three served as controls.

The rodents received 20 minutes of WBV each day of the week for 4 weeks. The WBV had a frequency of 30 Hz and an amplitude of 3mm. After the 4 weeks had ended, the team collected and analysed the rodents' adipose tissue. The researchers also performed similar experiments with WBV and assessed the rodents' microbiomes by examining their stool.

The experiments revealed various changes as a result of WBV. A crucial finding was a 17-fold increase in a gut bacterium called Alistipes that plays a key role in lowering inflammation in the gut. Previous research has found low levels of the bacterium in people with Crohn's disease and inflammatory bowel disease.

Among the short-chain fatty acids that Alistipes bacteria help release is butyrate, a metabolite of dietary fibre, which can reverse the negative effects of eating a high-fat diet.

Yu and Baban explained that Alistipes help ferment the food in the gut and improve metabolism in general, helping the body use sugar to create energy.

Furthermore, the experiments revealed that WBV resulted in an increase in M2 macrophages (immune cells that suppress inflammation) as well as increases in anti-inflammatory cytokines, such as interleukin-10, both in mice that had diabetes and in healthy mice.

In fact, in the mouse model of diabetes, WBV brought M2 levels back to those of healthy control mice.
Finally, the researchers wanted to see whether giving the mice small doses of Alistipes as a medication and combining it with a shorter session of WBV would have a therapeutic effect.

As soon as the population of this gut bacterium increased, the ratio between pro-inflammatory M1 macrophages and anti-inflammatory M2s also improved. ‘The sequencing is not yet completely clear’ said Yu, ‘but it appears to be a closed-loop, feed forward, self-magnifying cycle.’

Although more experiments are necessary to fully understand how an activity that mimics exercise without any of the active movement can have such a positive chain reaction, the researchers conclude that WBV can reduce inflammation and improve metabolism.

Source: Medical News Today