Low-carbohydrate diet score and risk of breast cancer: findings from a prospective cohort study

Table 4 Association between low-carbohydrate diet (LCD) score and risk of breast cancer after excluding incident cases and person-years in the first two years post-enrollment, the Singapore Chinese Health Study, 1993–2015

Characteristics	Person-year	# breast cancer cases	HR^a (95% CI)
Total LCD score
Q1 (lowest)	133,507	262	1.00
Q2	148,071	276	0.93 (0.78–1.10)
Q3	119,911	256	1.04 (0.87–1.24)
Q4 (highest)	147,305	245	0.79 (0.66–0.95)
P_trend			0.04
Continuous scale (per SD increment)			0.93 (0.88–1.00)
Animal-based LCD score
Q1 (lowest)	142,037	280	1.00
Q2	137,986	248	0.90 (0.75–1.06)
Q3	123,671	255	1.01 (0.85–1.20)
Q4 (highest)	145,101	256	0.85 (0.71–1.01)
P_trend			0.18
Continuous scale (per SD increment)			0.96 (0.90–1.02)
Plant-based LCD score
Q1 (lowest)	141,063	269	1..0
Q2	138,716	282	1.03 (0.87–1.21)
Q3	125,775	233	0.91 (0.76–1.09)
Q4 (highest)	143,239	255	0.85 (0.71–1.02)
P_trend			0.03
Continuous scale (per SD increment)			0.93 (0.88–0.99)

CI confidence interval, HR hazard ratio, LCD low-carbohydrate diet
^aModels adjusted for age at recruitment, education level, BMI (< 18.5, 18.5- < 23.0, 23.0- < 27.0, ≥ 27.0), dialect, year of enrollment, alcohol consumption status, number of children, menopausal status, age (year) when menstrual period became regular (< 13, 13–14, 15–16, or ≥ 17), family history of breast cancer, total energy intake