The aim of this study to investigate methodological aspects that may affect glycemic index (GI) and insulinemic (II) values. In addition, we will measure GI and II values for typical Finnish carbohydrate-rich foods and provide a database of GIs for Finnish foods.

The specific aims of this study are:

• to compare glycemic responses and GIs analyzed from capillary and venous blood to compare glucose against white bread as the reference food, and to study the effect of number of reference tests on GI values. For each setting of the tested parameters, we determined the glycemic indices of rye bread, oatmeal porridge and instant mashed potato
• to examine the glycaemic and insulinaemic responses of a mashed potato-based meal when a high fat food (rapeseed oil) or a high protein food (chicken breast) or fat, protein and salad together were added to the meal. Furthermore, we studied how the predicted and measured GI values of the mixed meal differed from each other.
• to examine the effects of two different coffee portions with glucose and caffeine-containing soft drinks on postprandial glucose and insulin responses. Further objectives were to study how coffee and different accompaniments affect glucose and insulin responses.
• to measure GI values for typical Finnish foods
• to study the effects of berries on glycemic and insulinemic responses
• to examine the effects of overweight and glucose tolerance on the glucose, insulin and lipid responses to an HGI meal and an LGI meal.Furthermore, the second aim was to study the effect of BMI and glucose tolerance on the GI measured.
• to compare methodological choices in insulin measurement
• to investigate the effect of alcohol on postprandial glucose and insulin responses, and to determine glycemic and insulinemic indices values for beer and non-alcoholic beer

Inclusion Criteria:

• For Studies 1-9 a total of 12 to 24 volunteers per study with a normal glucose tolerance based upon a 2 h 75g oral glucose tolerance test (OGTT).
• For Study 7 a total of 24 volunteers with impaired glucose tolerance based on an OGTT.
• For Studies 1-6 and 8-9 with an age of 20 to 60 and with a BMI of 18 to 30 kg/m2.
• For Study 7 an age of 62 to 72 and with a BMI of 20 to 35 kg/m2.

Exclusion Criteria:

• First-degree family history of diabetes
• An active gastrointestinal or metabolic disease
• For Studies 1-6 and 8-9 chronic medication (oral contraceptives were allowed)
• For Study 7 regular medication that would have affect glucose and lipid metabolism
• Smoking
• Pregnancy
• Breastfeeding
• History of polycystic ovary syndrome
• History of gestational diabetes