Long-term stress linked to higher risk of obesity
Research from University College London has concluded that people who suffer from long-term stress may be more prone to obesity. Researchers in this study analysed hair samples of 2,527 individuals aged 54 and older. They measured the levels of cortisol, known as the stress hormone, in these samples taking data over a four year period, they also measured BMI and waist circumference. They were then able to match the levels of cortisol to the persistence of obesity over time (as 2cm of hair represents approximately 2 months of growth).
They found that individuals with particularly higher levels of cortisol in their hair tended to have higher waist circumferences and BMIs. Chronic stress has been linked to obesity before, with people reporting overeating and ‘comfort eating’ high sugar and fat foods in times of stress, however this study has helped provide consistent evidence of this link. The study did have some limitations however, the data was from an exclusively older population, where levels of cortisol will be different to their younger counterparts, and causality cannot be interpreted from the results, only that there is a correlation. The researchers are therefore hoping to continue their research to further understanding in this area.
Read MorePhysical activity has higher benefit the older you are
The results of an observational study have been published in the European Journal of Preventive Cardiology. They show that the benefits of physical activity may outweigh the impact of obesity on cardiovascular disease. Data was collected on 5,344 individuals aged between 55 and 97, who were all free from cardiovascular disease at baseline. At the time, information on BMI, physical activity, smoking, alcohol use, diet, and education was taken. Over the course of 15 years the participants were followed and 16% of them suffered a cardiovascular event.
When the data was analysed it was found that physical activity was associated with a decreased risk of cardiovascular disease, regardless of what the individual’s BMI was. The results show that physical activity plays a crucial role in the health of middle aged and elderly people and is protective against the harmful effects of overweight and obesity. As the participants were all taken from The Rotterdam Study there were already parameters set for ‘low’ and ‘high’ amounts of physical activity, this was translated to two and four hours of daily activity – which itself included anything from biking to housework. The researchers hope to show that any physical activity is beneficial in terms of cardiovascular risk, even in those that are already normal weight or elderly.
Read MoreThe Swedish decline in childhood obesity
Data from Sweden has indicated that childhood obesity may be on the decrease in Sweden. A study has shown that the percentage of overweight and obese boys of 8 years old has decreased to it’s lowest level since the early 1990s. The researchers used data from the BMI Epidemiology Study (BEST) in Gothenburg, which has been collecting measurements from school health care systems for children born in 1946 onwards. In total, the study analysed data from 13 age groups of children born at five year intervals from 1946 to 2006. Each group consisted of 425, but this number was expanded when the researchers began to notice the reduction in obesity rates.
It was found that there was a clear reduction in mean BMI, overweight and obesity, however whilst this trend has been observed, the overall rates are still very high. The researchers are keen to point out that whilst they are not sure what has caused the decrease, we must continue on this trend in order to bring rates down even further. They also plan to conduct a similar study on girls in the near future.
Read MoreSugars can pass through breast milk
Researchers from the University of Southern California have found that fructose, a sugar that is linked to obesity and diabetes, can be passed from mother to baby via breast milk. The study itself involved 25 mothers and infants and also found that even a small amount of fructose daily could be associated with increased body weight. The sugar itself is found in fruit and processed food and beverages, it is not found naturally in breast milk, instead it is derived from the mother’s diet.
Exposing these children to higher amounts of sugar during growth and development can lead to problems with cognitive development as well as lifelong risks of obesity, diabetes, heart, and fatty liver disease. Unfortunately, the researchers of this study did not collect dietary data from the mothers so were unable to correlate the types of foods that the mothers consume to the levels of fructose in their breast milk, they are now undertaking this stage of their research. They are also keen to highlight the fact that caregivers should be aware and prepared to give advice to mothers about what sugars they do consume during pregnancy.
Read MoreExercise-induced hormone involved in bone metabolism
Irisin, a fat-burning, exercise-induced hormone has been shown to increase the formation and thickness of bone in mice. Researchers from Tufts University observed that after two weeks of voluntary wheel running mice expressed more of the hormone, further to this, when the hormone was administered systemically, the same bone effects were seen. This research is helping to further our understanding of how beneficial exercise might be for the skeletal system. Irisin has already been shown to convert white fat tissue into calorie-burning brown fat, it has also been shown to improve glucose intolerance, however little is known about where the hormone is produced.
The researchers in this study were able to isolate irisin and found that it was expressed in several different bone regions. They also found that irisin can directly increase the production of osteoblasts – cells that synthesise bone – and inhibit the production of osteoclasts – cells that break down bone. This study has shown that whilst irisin is capable of promoting the browning of white adipose tissue, it is also involved in the regulation of bone metabolism, the researchers are hoping to investigate it’s effects more thoroughly to assess its therapeutic potential.
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