Low Carbohydrate Diet From Plant or Animal Sources and Mortality Among Myocardial Infarction Survivors

BACKGROUND The healthiest dietary pattern for myocardial infarction (MI) survivors is not known. Specific long-term benefits of a low-carbohydrate diet (LCD) are unknown, whether from animal or vegetable sources. There is a need to examine the associations between post-MI adherence to an LCD and all-cause and cardiovascular mortality. METHODS AND RESULTS We included 2258 women from the Nurses' Health Study and 1840 men from the Health Professional Follow-Up Study who had survived a first MI during follow-up and provided a pre-MI and at least 1 post-MI food frequency questionnaire. Adherence to an LCD high in animal sources of protein and fat was associated with higher all-cause and cardiovascular mortality (hazard ratios of 1.33 [95% CI: 1.06 to 1.65] for all-cause mortality and 1.51 [95% CI: 1.09 to 2.07] for cardiovascular mortality comparing extreme quintiles). An increase in adherence to an animal-based LCD prospectively assessed from the pre- to post-MI period was associated with higher all-cause mortality and cardiovascular mortality (hazard ratios of 1.30 [95% CI: 1.03 to 1.65] for all-cause mortality and 1.53 [95% CI: 1.10 to 2.13] for cardiovascular mortality comparing extreme quintiles). An increase in adherence to a plant-based LCD was not associated with lower all-cause or cardiovascular mortality. CONCLUSIONS Greater adherence to an LCD high in animal sources of fat and protein was associated with higher all-cause and cardiovascular mortality post-MI. We did not find a health benefit from greater adherence to an LCD overall after MI.