Coffee, Phenolics and Potassium intake in Chronic Kidney Disease
Research type
Research Study
Full title
Coffee, phenolics and Potassium: dietary intake in Type 2 Diabetes Mellitus Subjects with Chronic Kidney Disease
IRAS ID
201240
Contact name
Susana Alejandra Palma Duran
Contact email
Sponsor organisation
NHS Greater Glasgow and Clyde
Duration of Study in the UK
1 years, 0 months, 0 days
Research summary
Potassium is found in most natural foods and it is particularly high in fruits, fruit juices, potatoes and vegetables which have not been boiled. In healthy adults, serum potassium levels are strictly regulated by the kidney irrespective of dietary intake. In subjects with diabetes mellitus, especially when there is a decreased clearance capacity of the kidney, the homeostasis mechanism for potassium may be reduced. However, it is not common for potassium homeostasis to be an issue until renal capacity is markedly reduced (with a glomerular filtration rate of 15 mL/min) when patients are approaching end stage renal failure or having to go on dialysis.\n\nAlthough, there are no published dietary recommendations for patients with moderately renal impairment (GFR of 30 – 59 mL/min), coffee and tea are sometimes restricted by their fluid volume, potassium and caffeine content. However, tea and coffee are listed in the low potassium group, containing 1.57±0.04 mmol (61.44 ± 1.38mg) of potassium per cup, while tea contains less than 2 mmol (78mg) per cup. Besides, drinking coffee (3–4 cups per day) has been associated with 25% lower risk of T2DM and 17% reduced risk. Polyphenols and melanoidin in coffee have presented antiglycative, anti-inflammatory, anti-carcinogenic and antioxidant properties, that may protect the kidney.\n\nHence, potassium intake should only be limited if blood tests show that is necessary (≥5.5mmol/L). In a regular coffee drinker, with an intake of 2-3 cups per day, potassium intake from coffee represents 2.0-10% of a normal potassium intake in adults (50–150 mmol/day). Therefore, potassium and sodium content in coffee does not represent a risk in moderately reduced renal function, where coffee and tea are not absolutely prohibited. The aim of the study is to evaluate potassium, beverage and polyphenols intake in diabetic patients with renal impairment, and compare the intake with healthy controls.
REC name
North of Scotland Research Ethics Committee 2
REC reference
16/NS/0052
Date of REC Opinion
31 May 2016
REC opinion
Further Information Favourable Opinion