Thinking yourself slim? Oh yes please!
It’s bad enough navigating the murky waters of the menopause, managing erratic cycles and coasting through emotional minefields, but gaining weight whilst doing so is not a menopausal symptom we relish. It hardly seems fair when the rest of life is speeding up to the point of insanity, our metabolism should be slowing down. In this porky, post-Santa, panicky phase of the year, when the realisation of the damage festive food has done on our waistlines starts to dawn (but before the actual dawns get any earlier or brighter to help us drown out the clamour of the left-over sweeties and cake, desperate for our attention…), a glimmer of hope peeks over the horizon with some research into our beliefs about food. Could it be true that how we think about a food influences its effect on us? Thinking ourselves slim? Surely not…
Now, to understand this study you first have to appreciate the role of a hormone called ghrelin. It is released by the stomach when we are hungry, and the more you have of it the hungrier you will be. When you have eaten sufficient amounts the levels of ghrelin you’re packing will decline and you’ll put the pudding down and walk away, no longer hungry. Hurray.
What this study was tackling was the enticing notion that maybe the amount of physiological (i.e. real, physical, in-the-flesh) satiation one experiences may vary depending on the mindset with which one approaches consumption of food. 
It involved a trick. Since when did good news about dieting ever not involve some kind of trickery?
46 participants were given a milkshake. They had previously been given a detailed description of two milkshakes, one containing 620 calories and one containing 140 calories, with the higher calorie one being billed as the ‘luxury’ one and the other the ‘healthy’ one. So half the group were given the luxury one and half the healthy one, and they were told quite frankly which they’d been given. Their levels of ghrelin and their feelings of hunger or satiation monitored. So far so sane.
You may not be surprised to know that those taking the high calorie shake had a far sharper decline in ghrelin and hunger levels than those whose shake was the low calorie one. Of course: that makes sense. Here’s the trick though. Both groups were actually taking a shake containing 380 calories. Same shake for both groups. Deep breath.
So the levels of satiety experienced were therefore being determined by the participants’ belief in the nature of the food they were consuming rather than the true nutritional value of that food. And it wasn’t just the way they were feeling; it was the actual level of ghrelin their stomachs were producing that was affected by their belief in the nature of the shake they had taken.
The researchers concluded that the effect of food consumption on ghrelin might be psychologically mediated. This means that your mindset may meaningfully affect physiological responses to food. Now, that doesn’t mean that you can bulldoze into the battenberg and see no ill effects on your silhouette so long as you firmly believe that it’s plain lettuce you’re eating. But it does mean that worrying over the calorific content of every mouthful, and visualising those biscuits stuck all over your hips in lumpy mounds of sinfulness, is doing you no good whatsoever. Not only is the food itself having its evil way with you, but the negative effect is increased by your thoughts about it.
And whilst you’re busy revising your New Year Resolutions to include daily mantras on the healthful nature of your diet, you may want to resolve to go vegan too. Don’t be scared: most of the food you eat is probably already vegan. Fruit and veg, nuts and seeds, dried fruit, beans, pulses, bread, crackers, oils, even dark chocolate, for goodness sake.
The reason for all this emphasis on the animal-free foodstuffs is that they are more likely to have a low glycaemic index (apart from the chocolate that is, sorry…). A study carried out by The Physicians Committee for Responsible Medicine and funded by the National Institutes of Health found that a vegan diet was better at controlling blood glucose and cholesterol, and reduced glycaemic index intake more than the 2003 American Diabetes Association (ADA) diet.  The glycaemic index intake predicted weight loss amongst the 99 participants, who all had Type II diabetes and therefore struggled with weight balance, so the researchers concluded that decreasing the intake of high glycaemic foods does help reduce body weight.
So we may be menopausal, but we have some New Knowledge to take us into the New Year – we can think nutritious thoughts as well as eat nutritious foods, and glory in our healthier minds as well as bodies!
 Crum AJ et al. Health Psychol. 2011 May 16. doi: 10.1037/a0023467
 Turner-McGrievy GM et al. J Nutr, In press