Last week I attended an interesting talk by Dr Sally Poppitt on appetite regulation. She works at the Nutrition Unit in Mt Eden, Auckland – a ten-bed live-in unit where she studies what and how much people eat. “For some of our studies we ask people to eat a test meal and then six to eight hours later eat an ‘ad lib’ lunch. That means they eat as much as they like, of whatever they like, from the free buffet – and we calculate what they have eaten,” she explained. “During those 6-8 hours we ask them to rate how hungry or full they feel”. Just as I was imagining the queue of volunteers attracted by the prospect of a free feed, she mentioned the blood tests. A plastic tube stuck into your arm so the researchers can take blood every hour would certainly stop me from volunteering!

I learned that it’s harder to regulate how many kilojoules you are consuming with liquids compared with solids. This explains why slurping on calorie laden thick-shakes, juices and fizzy drinks are so fattening – you don’t really cut back on the solid food to compensate. There is a similar effect from eating fatty foods – it confuses appetite regulation. Dr Poppitt described one of their studies where they gave overweight women a low fat meal (25% fat) and asked them to eat until they were full. A week later the women came back to the unit to eat exactly the same foods but this time, unknown to the women, the meal was high fat (50%fat). Dr Poppitt commented, “It’s really easy to pack fat into foods without noticing any difference”. On the low fat meal the women felt full and stopped eating at 3000kJ less than when they ate the high fat meal!

I unintentionally did a similar experiment this weekend. On Friday we ate out at our local Italian restaurant. The service is friendly and the food is delicious – just like being in an Italian kitchen with Mama cooking while the four of us enjoyed pizza, veal marsala, veal involtini, chicken parmigiana and a bottle of chianti. I chose the veal marsala which came with perfectly cooked vegetables. It was pretty low in fat and not a huge meal but I was full.

Two nights later came the second part of the experiment. Some of our family had booked us into the restaurant equivalent of the high fat all-you-can-eat buffet. Creamy soups, deep fried vegetables, garlic butter soaked bread, cheese laden pasta, chips, salads with rich creamy dressings and the desserts – rice pudding made with cream, whipped cream slapped onto commercial pavlova and stuffed into commercial brandy snaps, chocolate mousse, chocolate cake, buttery biscuits and slices. My son gleefully filled his dessert bowl with jelly beans, topped with serve-yourself-ice-cream, caramel sauce, chocolate sauce and sprinkles on top – twice!

It’s not really the place a dietitian gets excited about but we didn’t go for the food, we went to spend time with our family – and that was great. But I had to eat and, just as in Dr Poppitt’s study, after two or three visits to the buffet, despite fussily searching for the healthiest food, I’m sure I had eaten way more kilojoules than the veal marsala meal. Actually, I think it was the pavlova and brandy snaps that did it! Have you ever been in that situation where you don’t really like a food but you just keep on eating it? It’s the fat or sugar that does it, I’m sure!

So it’s back to proper food this week – rolled oats, organic sour dough grain bread, home-made hummus, salmon and rice, stir fried beef and vegetables, and apples and mandarins for dessert. My son will thank me one day!

Related:

Veal marsala recipe

Not healthy at all, but a New Zealand favourite, so here it is: Pavlova recipe