Research
Nutritional Epidemiology – Nita Forouhi
For decades it has been recognised that diet and nutrition are important in the management of people with type 2 diabetes and obesity. Now there is also evidence that a healthy and balanced diet is a key way of preventing the development of these conditions. It is still unclear, however, whether whole diets, dietary patterns or individual foods and nutrients are most associated with a person’s future risk of developing diabetes and obesity.
The goal of our research is to improve our understanding of the role that diet and nutrition play in the development of diabetes, obesity and related disorders. The specific objectives of our research are to:
- study the relationship between diet and nutrition and the risk of developing diabetes and obesity
- develop and use improved methods to assess diet
- understand the key determinants of dietary behaviour.
Traditionally, diet has been assessed in research studies by self-reported questionnaires such as the food frequency questionnaire. However, these can be associated with issues of possible under-reporting and measurement error. We aim to use methods with greater precision such as food records. These record food intake forward in time. We also use more objective, biological markers of nutrition, called nutritional biomarkers. For example, we can use blood levels of vitamin C as a biomarker for fruit and vegetable intake. We recently reported that the risk of developing new-onset type 2 diabetes was associated with decreasing blood levels of vitamin C, representing an objective biomarker of fruit and vegetable intake. However, the association of diabetes risk with fruit and vegetable intake that was self-reported through a questionnaire was weaker and less convincing. The development and use of other objective biomarkers of nutritional status will help us to address some of the previous uncertainties in nutritional epidemiological studies.
We are also examining the effects of eating habits or dietary behaviours on the risk of diabetes and obesity. We have reported that the risk of weight gain over time can be reduced by re-distributing the proportion of daily calories consumed at various stages of the day. By consuming the greater proportion of calories earlier in the day (eating breakfast), with a lower proportion of calories consumed later in the day, the risk of weight gain can be reduced. In new studies we are collecting information to assess the impact of snacking and eating outside of the home. We are also working with colleagues to understand the key determinants of dietary behaviour, and investigate how such determinants may modify the association between diet and disease.
For a full list of studies that the Nutritional Epidemiology Group is involved in click here.
