Lower carbohydrate and higher fat intakes linked to higher HbA1c

  • Churuangsuk C & al.
  • Eur J Nutr
  • 4 Nov 2019

  • curated by Sarfaroj Khan
  • UK Clinical Digest
Access to the full content of this site is available only to registered healthcare professionals. Access to the full content of this site is available only to registered healthcare professionals.

Takeaway

  • Lower carbohydrate and higher fat intakes are associated with higher glycated haemoglobin (HbA1c) and increased odds of having type 2 diabetes mellitus (T2DM).

Why this matters

  • Findings do not support low carbohydrate diets for prevention of T2DM.

Study design

  • This population-based cross-sectional study investigated whether carbohydrate intake and low-carbohydrate, high-fat (LCHF) dietary pattern relate to HbA1c concentration and T2DM prevalence (n=3234; diabetes diagnosis: n=104; without diagnosed diabetes: n=3130; aged ≥16 years).
  • LCHF scores (0–20, a higher score indicating lower % food energy from carbohydrate, with reciprocal higher contribution from fat) and UK Dietary Reference Value (DRV) scores (0–16, based on UK dietary recommendations) were calculated.
  • Funding: None disclosed.

Key results

  • Mean intake energy was 48.0% for carbohydrates, and 34.9% for total fat.
  • Every 5% food energy increase in carbohydrate and fat was associated with 12% lower risk of having diabetes (OR, 0.88; 95% CI, 0.78-0.99; P=.03) and 17% higher risk for diabetes (OR, 1.17; 95% CI, 1.02-1.33; P=.022), respectively.
  • Each 2-point increase in LCHF score was related to 8% (OR, 1.08; 95% CI, 1.02-1.14; P=.006) higher risk for diabetes, whereas there was no evidence for an association between DRV score and diabetes.
  • In those without diagnosed diabetes, every 5% energy increase in carbohydrate was associated with decrease in HbA1c percentage (−0.016%, 95% CI, −0.029 to −0.004%; P=.012), whereas every 5% energy increase in fat was associated with increased HbA1c percentage by 0.029% (95% CI, 0.015-0.043%; P<.001>
  • Each 2-point increase in LCHF score was related to higher % HbA1c (0.010%; 95% CI, 0.004-0.016%; P=.001), whereas each 2-point increase in the DRV score was related to lower % of HbA1c(−0.023%; 95% CI, −0.035 to −0.012%; P<.001>

Limitations

  • Risk of residual confounding.