Obesity Care

Impulsive personalities may lead to obesity

A new study conducted at the University of Texas at Dallas has found a link between impulsive personalities and the incidence of high body mass indices. The findings from this study have been published in Obesity. The study included 45 individuals and used different modalities to study their impulsivity such as self-reporting, neuropsychological testing and functional magnetic resonance imaging. By evaluating whether an individual’s decision making-style was more impulsive or cautious, using images on screens and measuring responses, the researchers were able to determine that participants with high BMI exhibited altered neural function compared to their normal weight counterparts.

The researchers originally thought that an inability to inhibit impulsive thoughts would be the driving factor behind the development of obesity, however it soon became clear that it was the inherent impulsive personality trait that is the mediating factor. Given these findings, the researchers hope that more will be done to develop treatments that provide coping skills or cognitive strategies for people to overcome impulsive behaviours. Further to this the increased self-awareness of impulsive behaviours may also help to control weight in certain individuals.

Couples with obesity take longer to conceive

Couples with obesity could take from 55 to 59% longer to conceive than their normal weight counterparts. This is the outcome of a study performed at the National Institute of Health. Many studies up until now have focused on the weight status of the potential mother, but this study looked at the impact of the father’s body composition as well. The study itself included 501 couples from across the USA and the follow-up period ran for four years.

The BMI status was measured for each couple and the probability of conception was also measured using a statistical measurement called fecunadbility odds ratio. Factors such as age, smoking status, physical activity, and cholesterol levels were accounted for and it was found that obese couples take far longer to conceive on average. The authors explain that fertility experts may want to take into account the weight status and body composition of both the male and the female when counselling about pregnancy.

Cancer mutation uses fat for fuel

New research published in Cell Metabolism has found that a certain melanoma mutation will cause the cancer to grow faster in a high-fat diet. The study was conducted on mice and found that cancers driven by a mutation in BRAF V600E (which is found in 60% of all melanomas) would thrive when the mice were given high-fat diets, alternatively, when they were fed lipid-lowering diets, the growth of the cancers slowed considerably. Most cancer cells display high glucose uptake, and recently low-carbohydrate diets have been tried as a therapeutic strategy against cancer. This research highlights that other factors could be at play, such as the BRAF V600E gene mutation; in this case a low-carbohydrate diet would not be helpful.

The research highlights the idea that diets can be specifically tailored to an individual’s needs, especially to prevent or delay tumour progression. Whilst human cancers can differ slightly in their metabolic properties, the researchers stress that this data could lead to more research into the designing of dietary regimens for cancer patients. At this point the researchers cannot be clear about which types of diets may trigger this, however they have managed to identify a compound known as acetoacetate as one of the triggers of this phenomenon, more research is being conducted.

Blood tests can help predict surgery outcome

New research suggests that by calculating the ratio of circulating fatty acids, we may be able to predict the outcome of bariatric surgery. The study examined whether the ratios of serum stearic acid/palmitic acid (S/P) would be a reliable marker in predicting diabetes remission and assessing metabolic status. Two independent cohorts were assessed, totalling 413 participants. It was found that patients who had a higher level of S/P before surgery had a greater chance of diabetes remission.

By adding S/P ratio to HbA1c levels and fasting C-peptide the predictive potential of these tests has increased significantly. A similar measure was found in the second cohort of patients, highlighting the possible use of S/P ratio as a novel marker in preoperative assessment. The researchers are hoping that this study could help inform healthcare providers on who would benefit most from bariatric surgery.

New detoxifying diet results in significant weight loss

Researchers from Skidmore College have developed a new ‘protein-paced’ diet (P-CR) that is based on consuming a low number of calories and intermittent fasting. They found that P-CR not only helps weight loss, but also enhances heart health, releases toxins from the body and reduces oxidative stress. P-CR itself involves consuming four to six meals a day, each with 20-25 grams of protein. The lead author, Paul Arciero, has also found that P-CR demonstrated sustained improvements in body weight, heart health and toxins when compared to traditional ‘heart-healthy’ diets.

Previous research has shown that weight loss can in fact release toxins into the blood, which is a natural reaction; P-CR is able to counter this by subsequently releasing those toxins from the body. Importantly, Arciero wanted to highlight that scientific evidence is now available that confirms that the quality of your diet matters, and through P-CR you can address a range of metabolic issues through diet alone.

Does obesity affect your memory?

A new study from Indiana University has found that memory training has only a third of the benefit to older adults with obesity than it does to their normal weight counterparts. The researchers followed cognition over a period of 10 years and compared the trajectories of a sample of adults. They are unsure as to the specific mechanism of this, with one hypothesis being that obesity reduces the size of the hippocampus, so there is less capacity for new memories. Approximately 2,800 individuals with an average age of 74 took part in the study.

Whilst much research has been done to develop weight loss programs, this research highlights the importance of protecting memory function, especially with the growing age of the population and the ever increasing rate of obesity. Different types of memory training were used in the study, such as memory, reasoning and speed of processing, but the largest change was seen in the memory field.

Teenage gastric bypass surgery and future complications

In a long term follow up study published in The Lancet Diabetes & Endocrinology it has been found that gastric bypass surgery helps severely obese teenagers keep weight off. The study aimed to assess the long-term effects of gastric bypass and any complications that were associated with this type of surgery. The study showed that whilst bypass surgery dramatically reduces teenagers’ weight, it could also lead to complications such as vitamin deficiencies. The researchers also found that, even though large weight loss had occurred, a third of the teenagers remained obese – meaning that earlier intervention may be needed along with lifestyle and dietary changes.

The lead author, Dr Thomas Inge, stressed that the study clearly showed the long-term benefits of bariatric surgery; however several nutritional risks have also been highlighted. The aim now is to focus on the health advantages whilst minimising these risks. It is clear that long-term follow up and care must be provided by centres that perform gastric bypass in teenagers, as the complications that follow could cause more problems in the future.

Inactivity breeds inactivity

A new study published in Cell Metabolism has found that inactivity leads to further decreased motivation to move. The study was conducted in mice and aimed to shed light on why people, or animals, with obesity were less active. The findings suggest that there is more to it than extra body weight being disabling. The study’s senior author, Alexxai V Kravitz, has a background in Parkinson research, and he was struck by how much Parkinsonian mice behaved like obese mice; he therefore hypothesised that the dopamine systems were dysfunctional in both groups. In this study, mice were fed either a normal or a high-fat diet for 18 weeks. They found that the high-fat diet mice began to move less before they gained the majority of their weight, suggesting that it was not excess weight alone that is responsible for this behaviour.

Dopamine is critical for movement and the researchers found that the obese mice had deficits in the D2 dopamine receptor. They were keen to point out that there are likely to be many other factors at play, but the deficit in D2 goes a long way to explaining the lack of activity. The researchers also studied the connection between inactivity and weight gain, to see whether it was causative. Kravitz explained that ‘in many cases willpower is invoked as a way to modify behaviour, but if we don’t understand the underlying physical basis for that behaviour, it’s difficult to say that willpower alone can solve it.’ Further to this, if we can discover the physiological causes as to why many obese people are less active, it may help reduce stigma towards them and help with the development of future treatments for obesity.

Sugar free drinks no better than full sugar drinks

With the UK introducing a levy on sugary drinks, expected to take effect in 2018, much research as to the effects of ‘sugar-free’ drinks is currently underway. One study from Imperial College London has found that sugar free drinks are no more helpful for maintaining weight than their full-sugar counterparts. Artificially-sweetened beverages (ASBs) are used as alternatives to full-sugar drinks and are often called ‘diet’ versions, to this end many consumers perceive them as the healthier option. However, this study found that there is no solid evidence to support this theory.

Sugar-sweetened beverages (SSBs) make up a third of UK teenagers’ sugar intake, and nearly half of all sugar intake in the USA, they contain few essential nutrients and have been proven to increase levels of obesity and diabetes. ASBs make up a quarter of the global sweetened beverages market; however they are not taxed to the same extent as SSBs, perhaps because of their perceived ‘healthiness’. The researchers suggest that ASBs might trigger compensatory food intake by stimulating sweet taste receptors and resulting in overconsumption of other foods. Whilst there is no direct evidence for a role of ASBs in weight gain, the researchers did not find any evidence suggesting that they were involved in weight loss when compared to their full sugar versions. The authors clearly stated that ASBs may be contributing to the global obesity crisis and should not be promoted as part of a healthy diet.

Eating routinely may help shed fat

A recent study was conducted at the University of Alabama to determine whether changing a person’s eating schedule could help them lose weight. This is one of the first human tests of early time-restricted feeding (eTRF) and it found that this type of meal timing can reduce swings in hunger and alter fat burning patterns. With eTRF people eat their last meal of the day by mid-afternoon and do not eat again until breakfast the next morning; essentially, the study suggests that eating during a much smaller window of time than one usually does can lead to weight loss. eTRF is associated with an 18-hour fasting period, the researchers claim that this keeps appetite levels more even throughout the day.
It is known that many aspects of the metabolism function to their optimum level at the beginning of the day; this diet seeks to exploit that and align with the circadian clock of the body. This study was conducted in 11 men and women with excess weight over four days, food intake was monitored as was calorie burning. Although eTRF did not alter the number of calories burned, it did reduce daily hunger swings and increased fat burning levels during night. This study was performed in a small sample size, therefore more research must be undertaken in this area in order to better understand its mechanisms and reliability.

Does good-tasting food directly cause weight gain?

A new study from the Monell Center in Philadelphia has found that desirable food in and of itself does not lead to weight gain. The study used mouse models in order to research the effects of good tasting food on overeating. Previous studies have shown that mice will show an affinity for tasty human foods such as chocolate chip cookies and crisps. However, this study aimed to examine whether the taste of food actually drives overeating. The researchers designed a series of experiments that assessed what types of food the mice liked; they then placed different groups of mice on a variety of diets. They found that the mice that ate the sweet and oily foods were no heavier than those that ate the plain foods.

These results were repeated over a period of six weeks, however food choice and overeating are complex mechanisms, many factors come in to play and therefore these results must be understood as being part of a much larger area of research. The study authors are hopeful that the results show that it is possible to create foods that are both healthy and good-tasting; however this research must be furthered to get to that point.

Vitamin D improves gut flora and metabolic syndrome

A study published in Frontiers in Physiology has found that a high-fat diet alone is not enough to trigger metabolic syndrome, it must be accompanied by a Vitamin D deficiency. Metabolic syndrome is defined by a group of risk factors that can lead to diabetes and heart disease, these include obesity, high blood sugar levels, high blood pressure and high cholesterol. The study itself was conducted in mice models and found that vitamin D deficiency caused an imbalance in gut flora, contributing to fatty livers and the symptoms that make up metabolic syndrome. Vitamin D deficiency can decrease the production of defensins, which are anti-microbial molecules that help to regulate gut flora.

If these outcomes can be repeated in humans it seems that exposure to the sun and consuming vitamin D supplements could be a feasible approach to preventing metabolic syndrome. The authors of the study are keen to continue this area of research so that more can be done to fully understand the role of vitamin D and vitamin D supplements in the development and prevention of metabolic syndrome.