‘The most important thing is that the basic diet is healthy and consistent with the guidelines of the Dutch dietary guidelines (Schijf van Vijf).’ Photo Shutterstock An unhealthy diet increases the risk of type 2 diabetes. ‘But what if you already have diabetes?’ wondered Iris van Damme. How can you prevent cardiovascular diseases then? She is due to get her PhD at the end of June for her research on healthy diets for this target group.
‘People with diabetes don’t always have a clear idea of what they should eat to keep their condition under control and prevent cardiovascular problems,’ explains Van Damme (Human Nutrition & Health). ‘Patients get dietary advice from their doctors and a lot of information can be found online, but many recommendations contradict one another.’
Van Damme did a literature search, collated all the evidence and analysed which diets are best for people with diabetes and their cardiovascular systems. Her conclusion: ‘An awful lot of diets can improve the health of this group. The most important thing is that the basic diet is healthy and consistent with the guidelines of the Dutch dietary guidelines (Schijf van Vijf). That’s encouraging because it also means many personal food preferences can be accommodated in one or other healthy diet.’
Pragmatic research
To test that knowledge in practice, Van Damme started a pragmatic intervention study. She assigned over 100 test subjects at random either to a control group, who continued as before, or an intervention group, who got guidance from a dietician for six months. ‘The dietician helped the participants to keep to a high-fibre, high-quality diet. We didn’t prescribe a standard diet. Instead, they all got personalized recommendations based on their eating habits. This meant everyone learned how to be a bit healthier in their own way. We wanted to know what effect that has on parameters such as their bodyweight, blood pressure and glucose values.’
She followed the participants for a year. In her thesis, she discusses the results from the first six months during which half of the test subjects visited a dietician. ‘We had hoped to see a change in dietary behaviour in the group that got guidance from the dietician. But unfortunately we found very few differences between the groups. Participants in the dietitian group did eat slightly healthier, but the differences were so small that we saw no improvements in their health values. This all shows how difficult it is to change dietary habits. Even giving people free access to a dietician doesn’t automatically result in healthier eating habits.’
Finger-wagging
She reflects on the studies she found in the literature. ‘Yet we are convinced that we can influence health with nutrition. If people regularly eat more plant-based food, or fewer carbohydrates or fats, that does improve their health. The difference between those studies and mine is probably down to the strictness of the researchers and the protocol. Often, the test subjects in those studies got pre-cooked meals to take home. We decided to do a study that stays close to real life and we largely left the dietician and test subjects in control. That fits in with how people make food choices these days.’
Based on her research and the conversations she had during the study with her test subjects, Van Damme concludes: ‘We mustn’t underestimate how difficult it is to eat more healthily. Sometimes society tends to wag its finger at people with diabetes: if you’ve got diabetes, you should simply eat more healthily and then the problem will soon go away. But it’s easier said than done.’
