This is the time of year when the battle of the bulge rages across the country. Yet again, we cut out the fat and know that this time it will be different. 1 Why do we start diets, only to fail? Or why we do lose the weight, only to discover it magically reappears again? Is it lardiness magnetism? There are many reasons why weight loss can be difficult – I have written a page on the subject. Just before Christmas, in New Scientist, I came across a very interesting article about the complex interaction between the gut and the brain. There was a section about the effect of fat in the stomach upon feelings of hunger, emotion and fullness which may make us pause as we reach for that low fat yoghurt.2
The article referenced a study done on human volunteers in which a dose of either the fat called lauric acid3 or a dose of saline was put directly into the gut via a tube and they were then played sad music whilst being shown sad expressions or they were played neutral music whilst being shown neutral expressions. The subjects were asked about their feelings of hunger, sadness and mood and these were backed up by brain scans. Click on the link to see the tables of results.
What is interesting is that those with the saline in their stomach felt considerably more hungry, sadder and least full when subjected to the sad music and faces. However, when exposed to neutral music they felt a bit less hungry and sad than those with fat in their stomach. But those with the fat in their stomach still felt fuller than the saline group when exposed to neutral music.
Of course, sorrow is only one form of stress. The experiment did not look at anger or frustration’s effect upon mood and hunger. In the immediate aftermath of getting very angry, eating is not normally high on the list of things to do. No, eating kicks in much later, as the wonderful book by Robert Sapolsky, Why Zebras Don’t Get Ulcers goes into. Nevertheless, all negative emotions raise the stress hormones and from this experiment, it seems that to include fat in the diet reduces the emotional roller coaster. So being ‘good’ and eating a low fat cereal for breakfast, with low fat milk and maybe some fruit will be fine provided the day is nice and calm. But if we look in the mirror and realise we’re are having a bad hair day or discover our favourite team has lost a critical match, then we are going to feel much more emotional and more prone to an accident with the biscuit barrel following such a breakfast than if we’d eaten a nice round of bacon and eggs. 4
In summary, if we know that we like a bit of comfort eating, then making sure that every meal contains a natural amount of fat5 will help reduce the emotional highs and lows of a normal day and keep us in control of our food choices.
- Insanity defined: keep doing the same thing and expect a different result. [↩]
- The Journal of Clinical Investigation, vol 121. p 3094 [↩]
- Lauric acid is found in coconut oil and in human breast milk. It is a medium chain triglyceride, so easily digestible and less likely to be turned into body fat than other fats. A point worth bearing in mind when coconut oil is being slammed for being a saturated fat. [↩]
- There is a famous study called the Framingham Heart Study which found that those who ate bacon and eggs for breakfast – and smoked! – were less prone to heart attacks than those who ate cereal for breakfast. Frustratingly, the results are buried deep in the data, so are exceedingly hard to dig out. [↩]
- A natural amount of fat. So if we have a salad, add a french dressing WITH olive oil or avocado oil. If we want yoghurt, have a full fat yoghurt. If we must drink milk, then drink normal, full fat milk – its still only 5° fat, after all. If we eat cheese, eat normal cheese, not some appalling low fat, fiddled with, alternative. It is not the fat that makes us fat, it is the excessive carb intake: too many cakes or chips. [↩]