The Western pattern diet is a modern dietary pattern that is generally characterized by high intakes of pre-packaged foods, refined grains, red meat, processed meat, high-sugar drinks, candy and sweets, fried foods, industrially produced animal products, butter and other high-fat dairy products, eggs, potatoes, corn (and high-fructose corn syrup), and low intakes of fruits, vegetables, whole grains, pasture-raised animal products, fish, nuts, and seeds.
[4] This diet is "rich in red meat, dairy products, processed and artificially sweetened foods, and salt, with minimal intake of fruits, vegetables, fish, legumes, and whole grains.
"[5] Various foods and food processing procedures that had been introduced during the Neolithic and Industrial Periods had fundamentally altered 7 nutritional characteristics of ancestral hominin diets: glycemic load, fatty acid composition, macronutrient composition, micronutrient density, acid-base balance, sodium-potassium ratio, and fiber content.
[7] These macronutrient intakes fall within the Acceptable Macronutrient Distribution Ranges (AMDR) for adults identified by the Food and Nutrition Board of the United States Institute of Medicine as "associated with reduced risk of chronic diseases while providing adequate intakes of essential nutrients," which are 45–65% carbohydrate, 10–35% protein, and 20–35% fat as a percentage of total energy.
USDA research conducted in the mid 2010s suggests that the average intake of American adults is at least 2,390 kcal (10,000 kJ)[11] per day.
[15] Americans ages 1 and above consume significantly more added sugars, oils, saturated fats, and sodium than recommended in the dietary guidelines outlined by the Office of Disease Prevention and Health Promotion.
[17] Margarine is produced by refining vegetable oils, a process that introduces trans elaidic acid not found naturally in food.
As populations become more affluent, reflected in a growing GDP, they have more disposable income to purchase food from other countries, which facilitates this dietary transition.
When this occurs, populations substitute a low-calorie and vegetable intense diet for more energy-intensive products that are characterised by increase in meat and refined fats, oils and sugar consumption.
[27] Crohn's disease has its effects on the symbiotic bacteria within the human gut that show a positive correlation with a Western pattern diet.
[28] There is a positive correlation between a Western pattern diet and several plasma biomarkers that may be mediators of obesity, such as HDL cholesterol, high levels of fasting insulin, and leptin.
[30] Several studies have shown that there is a positive correlation between adoption of a Western pattern diet and incidence of type 2 diabetes among both men[28] and women.
Overall dietary consumption in these regions now reflects a higher balance of processed sugars and fats over lower-calorie food groups like vegetables and starches.
[42] The Neolithic Revolution introduced the staple foods of the western diet, including domesticated meats, sugar, alcohol, salt, cereal grains, and dairy products.