Research
The research of HELGA is centered around some research strategies in the investigation of the impact of whole grains on disease occurrence and prognosis.
(Click on image for larger version)
- Epidemiology
- Intake of whole grain and whole grain products in relation to disease incidence and survival
- Biomarkers of intake (alkylresorcinols and aventhramides), internal dose (enterolactone, enterodiol, alkylresorcinols, acrylamide, cadmium and mycotoxins)
- Anthropology
- Clinical intervention studies
- Metabolomics
Epidemiology
A large, central database has been established based on three Nordic cohort studies in Tromsø, Umeå and Copenhagen: The Norwegian Women and Cancer study, The Northern Sweden Health and Disease Study and the Danish Diet, Cancer and Health study. All three cohorts are part of the European Prospective Investigation into Cancer and Nutrition. The participants were recruited from the general population, but the Norwegian study only included women. At baseline (1992-1998), the participants filled in a questionnaire regarding their habitual food intake and lifestyle. The full HELGA cohort includes a total of 120,016 participants.
Whole grain intake
In the common database, the intake of whole grain has been estimated and will be used to study associations between whole grain intake and a range of diseases. Research in HELGA have so far primarily concentrated on associations between intake of whole grain foods and incidence of breast and prostate cancer and diabetes. These diseases will still have a high priority in future research, but also studies on other cancers (endometrial and colorectal), myocardial infarction and total mortality will be included.
Biomarkers
Alkylresorcinols and aventhramides can potentially be used as biomarkers for intake of whole grain rye, and wheat and oat, respectively, and can be used as unbiased measures for quality and quantity of whole grain intake. The quality of these biomarkers and their ability to predict whole grain exposure will be tested in blood samples from the epidemiological cohort studies and the intervention studies. Furthermore, the alkylresorcinols will be used as an exposure measurement of the whole grain intake in prospective studies with cancer endpoints (endometrial cancer and colorectal cancer).
Enterolactone and enterodiol are phytoestrogens originating from precursors in all foods of vegetable origin; particularly whole grains are rich sources. Enterolactone and enterodiol have inherent disease preventing effects and high blood levels of these substances may decrease the incidence of disease. The ability of a diet containing high levels of the enterolactone and enterodiol precursors to prevent occurrence and development of serious diseases will be evaluated in epidemiological studies.
Acrylamid, cadmium and mycotoxins originating from whole grain foods may have negative effects on human health. Whole grain foods are predominantly ascribed health promoting effects but the mentioned substances are presumed undesirable contents of some whole grain products. To evaluate the health problems associated with these substances and subsequently be able to diminish their impact, it is necessary to gain further knowledge of their health consequences. Biomarkers of acrylamid, cadmium and mycotoxins originating from whole grains will be investigated in relation to the incidence of cancer.
Information about biomarkers of dietary intake including alkylresorcinols (biomarker of whole grain rye and wheat) can be found on the homepage of the Swedish University of Agricultural Sciences.
Sami diet score
The influence of various dietary patterns, such as the Mediterranean diet and high-protein, low carbohydrate diets, on health has received considerable attention in recent years. The Sami people, indigenous people of Scandinavia and Northern Finland, are known to have a lower incidence of total cancer and a somewhat different incidence pattern concerning cardiovascular disease compared with non-Sami people. Previous studies have reported a high level of physical activity, a high intake of boiled coffee and protein, and a low intake of fiber and whole grain as characteristics of the traditional Sami lifestyle. A project will relate the traditional Sami diet pattern, and selected dietary elements typical to the Sami lifestyle, to the risk of cancer and cardiovascular endpoints in population-based data from Northern Sweden, Norway and Finland.
Anthropology
Anthropology provides a qualitative approach to lifestyle and consumer choice that seems to go against 'better knowledge'. To assess dietary preferences, detailed empirical studies of social values and hierarchies of knowledge will complement the quantitative and biological studies.
Clinical intervention studies
The role of whole grain in prognosis of patients, especially after cancer, is an area of increasing interest. Therefore, a Nordic randomized, multi-center, clinical trial in Sweden, Iceland and Denmark will be conducted, investigating the effect of an intensive lifestyle intervention on whole grain and physical activity according to progression of prostate cancer, quality of life, bodily awareness and individual empowerment, and the metabolic profile among men on active surveillance with early-stage prostate cancer. First, however, a feasibility study will be conducted in Denmark to see whether it is possible to enroll participants for a lifestyle intervention including a health-promoting diet high on rye combined with a high level of physical activity among this particular patient group.
Another intervention study, conducted in the Baoshan area of China, aims at exploring the impact of bread containing whole grain rye and rye bran on prostate cancer progression in prostate cancer subjects, and whether associations exist between dietary intake of alkylresorcinols, tocopherols/tocotrienols and lignans and their respective urinary excretion and blood concentrations. Also, the impact of bread containing whole grain rye and rye bran, with or without fermentation, on H. Pylori infections and on various metabolic factors associated with metabolic syndrome will be investigated.
Metabolomics
Consumption of whole grain foods is convincingly associated with reduced incidence of serious ailments like diabetes and cardiovascular diseases. However, the mechanisms of their protective effect remain unknown. A diet rich in whole grain cereals is studied by focusing on the analysis of small bioactive metabolites, by applying methods including biomarker screening and metabolite profiling (LC-MS) on sample sets of urine and plasma from intervention studies with different compositions of whole grain rye versus white wheat. Other topics are to monitor the effect of food derived compounds on cell cultures; to identify components most responsible for the health beneficial effect of plant rich diet and changes driven at the cellular metabolism by plant borne components; to gain insight into the alterations occurring on the bioactive compounds in human metabolic system; and to increase the understanding of the health potential of whole grain foods.
Another study on metabolomics will investigate whether consumption of rye bran can change the profile of metabolites in plasma and urine of prostate cancer subjects and identify a biomarker of rye bran consumption following an intervention with prostate cancer subjects and healthy participants. NMR and LC-MS based metababolomic data produced by analysis of plasma and urine will be used as well as multivariate statistic for the analysis of NMR and LC-MS based metabolomic data. Principle component analysis (PCA), Orthogonal partial least squares-discriminant analysis (OPLS-DA) will be applied.