The SAD is a diet high in processed foods, saturated fats, and carbohydrates.

According to the Centers for Disease Control and Prevention (CDC), most individuals in the U.S. do not eat a healthy diet, consuming too much saturated fat, sugar, and sodium.

Components

People consuming the SAD may have a high intake of the following:

• sodium
• red meats
• trans fats
• saturated fats
• processed meats
• refined grains
• high fat dairy products
• sugar-sweetened beverages
• ultra-processed foods (UPFs)
• alcohol

Healthy diet components

The SAD is not a balanced diet.

According to the Dietary Guidelines for Americans, 2020–2025, it is best to eat a diet that includes nutrient-dense foods and beverages from across various food groups.

A healthy dietary pattern may include:

• grains, half of which are whole grains
• fruits in all colors, especially whole fruits
• vegetables in a variety of colors, including beans, peas, and lentils
• fat-free or low fat dairy products, such as milk, yogurt, cheese, or lactose-free alternatives
• lean protein, such as poultry, eggs, seafood, nuts, and soy products
• healthy fats, such as olive oil, nuts, and avocado

A balanced diet ensures people get all the essential nutrients required to maintain good health.

However, the SAD is low in several vital micronutrients, which may lead to impaired immune function and negatively affect health.

The following percentages of the U.S. population have inadequate levels of key immune-related micronutrients:

• Vitamin A: 45%
• Vitamin C: 46%
• Vitamin D: 95%
• Vitamin E: 84%
• Zinc: 15%

As well as the items in the list in the previous section, people can aim to include the following in their diet to meet their daily nutrient requirements:

• oils
• seeds
• lean meats
• seafood

Eating the SAD over a long period can contribute to the development of certain conditions, including the following:

Overweight and obesity

According to the CDC, obesity affects around 41.9% of adults and 19.7% of children and adolescents in the U.S. Obesity occurs when energy intake from food is significantly higher than energy expenditure from physical activity, causing a person to gain weight.

Many factors — such as genetics, activity levels, and socioeconomic status — contribute to obesity. One significant factor includes the types and amounts of foods and beverages a person consumes.

The SAD includes vast amounts of UPFs, which are high in calories, sugar, salt, and fat and contain minimal whole foods. Examples of UPFs include:

• white bread
• sweetened breakfast cereals
• savory snacks
• candy
• cookies
• cakes
• ice cream
• pizza with fatty processed meat toppings
• sausages, lunch meats, and bacon

Research suggests that consuming large quantities of UPFs may play a significant role in obesity.

A 2019 study found that a diet with large proportions of UPFs increases energy intake and results in weight gain. The study data suggest that eliminating these foods from the diet decreases energy intake, leading to weight loss.

Learn more about obesity.

Heart disease and stroke

Heart disease is the leading cause of death in the U.S.

In 2021, 1 in 6 deaths from heart disease were due to stroke.

Certain diet-related factors can increase a person’s risk of heart disease and stroke. These may include consuming the following:

• a diet high in cholesterol, saturated fats, and trans fats
• a high intake of added sugars
• too much sodium
• too much alcohol

A low quality diet also contributes to other conditions that raise a person’s risk of heart disease and stroke, such as:

Research indicates that the SAD is a significant risk factor for heart disease and stroke.

Another 2021 analysis examined the link between fried foods in the Western diet and heart disease. Compared with the lowest levels of consumption, high levels of fried food consumption were associated with:

• a 28% higher risk of major cardiovascular events, such as heart attack or stroke
• a 22% increased risk of heart disease
• a 37% heightened risk of heart failure

Type 2 diabetes

Around 1 in 10 people in the U.S. have diabetes, with approximately 90–95% having type 2.

People typically have an increased risk of type 2 diabetes if they are overweight or have obesity.

A 2023 research model of dietary intake suggests there could be a significant link between type 2 diabetes cases and diet. The researchers note that an insufficient whole grain intake and excessive consumption of refined rice, refined wheat, and processed meat may significantly contribute to the condition.

A 2022 publication also suggests that Western diets high in fructose and fat may damage insulin-producing pancreatic beta cells, increasing the risk of type 2 diabetes.

Cancer

The SAD may increase the risk of certain types of cancer.

Research suggests that while Western diets high in red meats, fat, and added sugars tend to increase the risk of excess body fat and obesity, the Mediterranean diet may reduce the risk.

According to the CDC, there is an association between overweight and obesity and a higher risk of 13 cancer types, including:

Individuals may be able to maintain a moderate weight and lower their risk of obesity-related cancers by following a healthy eating plan and getting regular physical activity.

Learn more about cancer.

Social and economic factors impact the dietary choices available to individuals in a community. These factors may include income, education, employment, and social support.

A 2022 analysis of 155,331 adults found that multiple social, economic, and geographical factors were associated with a poor diet. The researchers observed a poorer diet quality more frequently among study participants who:

• were younger
• were Native American, Alaska Native, or Black
• had lower income and educational levels
• lived in a nonmetropolitan area
• lived in a food desert, a place where residents have limited access to healthful foods
• had never married
• worked full time
• had obesity
• reported minimal exercise
• smoked tobacco
• consumed less alcohol
• had two or more chronic medical conditions
• were less likely to cook at home and more likely to buy meals from fast-food and full-service restaurants

These findings can help identify communities at the highest risk of adverse outcomes from poor diet to determine future strategies toward reaching health equality.

Learn more about food deserts.

The Western diet, or “standard American diet” (SAD), is the dietary pattern of many people in the U.S. It is high in saturated fats and refined carbohydrates. It is low in fruits, vegetables, and other plant-based foods.

The SAD provides inadequate levels of micronutrients, which may lead to deficiencies in zinc and Vitamins A, C, D, and E. Research also links SAD with health conditions such as obesity, heart disease, and stroke.

There are links between many socioeconomic factors and a poor diet, including having a low income and living in a rural area. Knowing these factors, experts need to formulate strategies to improve dietary options across communities.