When statistically derived using PCA or factor analysis, usually multiple dietary patterns were reported. Two researchers (NL and LX) independently grouped all dietary patterns into three categories: healthy, unhealthy, or neutral, based on constituent foods of each pattern suggested by PCA or main factor loadings. Any disagreements were discussed with the senior researcher (JM). Table 1 shows dietary patterns, categories, and constituent foods. A healthy dietary pattern was characterized by high intakes of fruit, vegetables, whole grains, and/or fish. An unhealthy dietary pattern tended to have high loadings of refined grain, red meat, processed meat, fast foods, high sugar foods, and/or high fat foods. A neutral dietary pattern generally consisted of a mixture of healthy and unhealthy food items. The same two researchers (NL and LX) independently extracted the data to be used for meta-analysis.