Facile fingerstick insulin analysis: Application to monitoring postprandial insulin responses to snack foods

Abstract

Background: Energy intake from snacks has been increasing in the American diet, but insulin and glucose responses to foods are generally reported for meal‐sized portions (800–1200 kJ). Established methods for insulin determination routinely use indwelling catheters and radioimmunoassay (RIA). The aim of the present study was to develop a more facile method, collecting fingerstick blood samples and measuring insulin with precise ELISA, and then applying this method to determine responses to snack‐sized food portions. Methods: Six healthy, fasting adult volunteers consumed seven different snack foods on separate days, containing approximately 400 kJ/portion. Insulin was measured by ELISA and glucose was measured with the hexokinase procedure in samples collected by fingerstick at 0, 30, and 60 min after consumption of the snack food. Results: A portion of doughnut (half a glazed doughnut) led to marked changes in insulin and glucose; skim milk, an apple, and oatmeal changed insulin significantly; wrinkled peas resulted in a lower glucose response than smooth peas; and walnuts led to non‐significant changes in both insulin and glucose over a 60‐min period. Conclusions: The fingerstick sampling and insulin measurement procedure is simple, economical, and more precise than established RIA. The method can be applied to children and adults to monitor insulin responses following food consumption, as well as during therapeutic assessments or intervention trials. Public health advisories regarding snacks that minimize increases in insulin are desirable for individuals trying to reduce or maintain their weight, because elevated insulin stimulates carbohydrate conversion to fat and suppresses the mobilization of stored triglycerides for energy generation.

Rapid screening of sixty potato cultivars for starch profiles to address a consumer glycemic dilemma

“…These comparisons can be seen in Table 5 . These results agree with other observations with potatoes [ 39 ] and peas, as high amylose peas are more wrinkled and cause a much lower insulin response in humans than smooth peas [ 40 ]. The wrinkled peas also have a lower capacity to absorb water [ 41 ].…”

“…Nutrition data indicates that consumption of potatoes with higher concentrations of amylose is expected to have a lower Glycemic Index and would be expected to provide health benefits for people that have prediabetes, diabetes and/or obesity. A lower sugar release during digestion due to differences of digestibility of amylose and amylopectin is expected to cause a lower sugar spike and lower release of insulin [ 4 , 12 , 32 , 40 , 42 ]. Furthermore, high insulin release tends to lead to an undershoot in desirable blood sugar levels (hypoglycemia), stimulating hunger, increased food consumption and potential weight gain, as illustrated in Fig 1 .…”

“…This rapid screening system will potentially foster elevation of nutrition as a priority in plant breeding. This work now will be followed by glycemic index measurements and agronomic fitness [ 40 , 43 , 44 ] on the most promising potato varieties.…”