This week’s podcast focuses on the intricate relationship between obesity and the brain. We will be answering questions such as:
Why is it so difficult to lose weight, even when you eat less?
Professor Simon Luckman discusses how our brain regulates energy balance. We find out how the brain receives information on energy status through a variety of different signals, such as nerve fibres sending signals from our gut or via the release of hormones such as leptin. Leptin is released from our fat stores to let the brain know how much energy we have in reserve. We also discuss how our body expends energy, and whether it is possible for us to simply increase our energy expenditure in order to counteract an increase in food intake. In an extended interview, I discuss the hormone irisin with Simon. This hormone is released by skeletal muscle and has been shown to increase energy expenditure upon both cold exposure and exercise and has recently been deemed by the media as a ‘weight loss’ hormone.
Since the dutch famine, it has been noted that there is an association between maternal undernutrition and the propensity for the offspring to go on to develop obesity in later life. We speak to Profesor Anne White about how maternal undernutrition could be causing the offspring to develop obesity, and why this system may have evolved. We discuss where changes may be taking place in the foetus that lead to obesity in offspring in later life, and what these changes might be.
Is being obese harmful to the brain?
Finally, we discuss how obesity can affect brain diseases such as alzheimer’s and stroke with Dr Catherine Lawrence. It is thought that being obese mid-life can have negative impacts on the timing and development of the disease Alzheimer’s. We discuss what mechanisms may be underlying the observed relationship between obesity and alzheimer’s. It is also known that in the lab, obesity not only leads to an increase risk of stroke, but also can affect the outcome and prognosis after a stroke. We speak to Catherine about the work she is involved with in identifying what could be causing obesity to influence stroke outcome, and why this negative relationship between obesity and stroke outcome is not always seen in the clinic.