TABLE 1.

Characterization of most investigated a priori– and a posteriori–defined dietary patterns in relation to neurodegeneration¹

Dietary pattern (ref)	Characterization
A priori (hypothesis driven approach)
MeDi (25)	Based on traditional eating habits in Crete, south Italy, and other Mediterranean countries
	• High in fruits, vegetables, cereals, and legumes
	• Low in saturated fats; olive oil main fat source
	• Moderate in fish
	• Low to moderate in dairy products
	• Low in red meat and meat products
	• Moderate in alcohol (wine)
HDI (21)	Based on WHO recommendations for the prevention of chronic diseases
	• SFAs: ≤10en%
	• PUFAs: 3–7en%
	• Protein: 10–15en%
	• Complex carbohydrates: 50–70en%
	• Dietary fiber: 27–40 g/d
	• Fruits and vegetables: >400 g/d
	• Pulses, nuts, and seeds: >30 g/d
	• Oligo-/mono- and disaccharides: ≤10en%
	• Cholesterol: ≤300 mg/d
HEI (23)	Based on the food patterns found in MyPyramid and is a sum of 10 individual components
	• Adequacy of total whole fruits, vegetables, dark-green and orange vegetables and legumes, total grains, whole grains, milk, meat and beans, oil
	• Low intakes of saturated fat, sodium, and calories from solid fats, alcoholic beverages, and added sugars
RFS (22)	Based on the Dietary Guidelines for Americans and calculated as the sum of 23 items that are consumed at least once a week
	1) Apples or pears; 2) oranges; 3) cantaloupe; 4) orange or grapefruit juice; 5) grapefruit; 6) other fruit juices; 7) dried beans; 8) tomatoes; 9) broccoli; 10) spinach; 11) mustard, turnip, or collard greens; 12) carrots or mixed vegetables with carrots; 13) green salad; 14) sweet potatoes, yams; 15) other potatoes; 16) baked or stewed chicken or turkey; 17) baked or broiled fish; 18) dark breads, such as whole wheat, rye, or pumpernickel; 19) cornbread, tortillas, and grits; 20) high-fiber cereals, such as bran, granola, or shredded wheat; 21) cooked cereals; 22) 2%-fat milk and beverages with 2%-fat milk; 23) 1%-fat or skim milk
DASH trial (24)	Based on intakes of nutrients hypothesized to alter blood pressure
	• Rich in fruits and vegetables
	• Rich in low-fat dairy food
	• Reduced amounts of saturated fat, total fat, and cholesterol
French National Nutrition and Health Program (PNNS-GS) (20)	Based on French National Nutrition and Health Program recommendations to improve the health status of the general population
	• Fruits and vegetables at least 5 servings/d
	• Bread, cereals, potatoes, and legumes at each meal
	• Choose whole-grain food and whole-grain bread more often
	• Milk and dairy products 3 servings/d
	• Meat and poultry, seafood, eggs 1–2 servings/d
	• Seafood at least twice per week
	• Limit consumption of added fats
	• Favor fats of vegetable origin
	• Drink water as desired
	• Limit sweetened beverages
	• Limit salt consumption
	• At least 30 min of brisk walking or equivalent per day of physical activity
A posteriori (exploratory approach)
Cluster analysis (3, 7, 27)	Classification technique, which aggregates subjects with similar defined variables such as dietary pattern and the energy contribution of each food group
PCA (7, 15)	Common approach of factor analysis to define dietary patterns, aggregates highly correlated food items to identify underlying dietary patterns
RRR (7, 26, 28)	Mix of an exploratory and hypothesis-driven approach, involves the elements of an a priori approach to derive dietary patterns

¹DASH, Dietary Approaches to Stop Hypertension; en%, percentage of energy intake; HDI, Healthy Diet Indicator; HEI, Healthy Eating Index; MeDi, Mediterranean diet; PCA, principal component analysis; PNNS-GS, Program National Nutrition Santé guideline score; ref, reference; RFS, Recommended Food Score; RRR, reduced rank regression.