No effect of bicarbonate treatment on insulin sensitivity and glucose control in non-diabetic older adults.
Chronic mild metabolic acidosis is common among older adults, and limited evidence suggests that it may contribute to insulin resistance and type-2 diabetes. This analysis was conducted to determine whether bicarbonate supplementation, an alkalinizing treatment, improves insulin sensitivity or glucose control in non-diabetic older adults. Fasting blood glucose and insulin were measured in stored samples from subjects who had completed a 3-month clinical trial of bicarbonate supplementation to improve indicators of bone and muscle health. One hundred and fifty three ambulatory, non-diabetic adults aged 50 years and older were studied. Subjects were randomized to one of two bicarbonate groups (67.5 mmol/day of potassium bicarbonate or sodium bicarbonate) or to one of two no-bicarbonate groups (67.5 mmol/day of placebo or potassium chloride). Subjects remained on treatment throughout the 3-month study. The primary outcome measures were changes in fasting plasma glucose, serum insulin and HOMA-IR, an index of insulin resistance. Bicarbonate supplementation reduced net acid excretion (adjusted mean±SEM for the change in NAE/creatinine, mmol/mmol, was 0.23±0.22 in the no-bicarbonate group compared with -3.53±0.22 in the bicarbonate group, P<0.001) but had no effect on fasting plasma glucose, serum insulin, or HOMA-IR. In conclusion, bicarbonate supplementation does not appear to improve insulin sensitivity or glucose control in non-diabetic older adults.
Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington St., Boston, MA 02111, USA. susan.harris@tufts.edu
Susan S
SS
Harris
Bess
B
Dawson-Hughes
D000138:Acidosis / Q000188:drug therapy* / Q000378:metabolism; D000368:Aged; D001786:Blood Glucose / Q000187:drug effects* / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000517:prevention & control*; D005260:Female; D005500:Follow-Up Studies; D006706:Homeostasis / Q000187:drug effects; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D010919:Placebos; D017693:Sodium Bicarbonate / Q000008:administration & dosage*; D017211:Treatment Failure
D001786:Blood Glucose; D007328:Insulin; D010919:Placebos; D017693:Sodium Bicarbonate