What are solid fats in the American diet?

December 22, 2025 •

3 min read

According to the Dietary Guidelines for Americans, more than 80% of the U.S. population exceeds the recommended limit for saturated fat intake. Solid fats, which are a major source of saturated and trans fats, are found in many common foods in the American diet. Understanding these fats and their sources is critical for making healthier dietary choices.

Quick Summary

Solid fats are those solid at room temperature, primarily consisting of saturated and trans fats found in many animal products and processed foods. Excessive intake of these fats can raise LDL ("bad") cholesterol, increasing the risk of heart disease and contributing to weight gain. Reading food labels and making mindful substitutions are key to limiting solid fat consumption.

Key Points

Definition: Solid fats are those that are solid at room temperature, such as butter, lard, and shortening.
Sources: Major sources include animal products like fatty meats and full-fat dairy, as well as processed and fried foods.
Fat Composition: They are primarily made up of saturated and trans fats, which differ chemically from the unsaturated fats found in oils.
Health Risks: High intake of solid fats can increase LDL ("bad") cholesterol, raising the risk of heart disease, stroke, and contributing to obesity.
Dietary Shift: Health experts recommend replacing solid fats with healthier, unsaturated oils like olive and canola oil.
Label Reading: Checking nutrition labels for saturated fat content and avoiding ingredients like "partially hydrogenated oils" is a key strategy for reduction.
Cooking Alternatives: Simple cooking changes, such as grilling or baking instead of frying, can drastically lower solid fat intake.

Understanding Solid Fats and Their Composition

Solid fats are defined by their physical state at room temperature; they remain solid, unlike liquid oils. Their firmness stems from a chemical structure saturated with hydrogen atoms, allowing tight packing. Saturated fat and trans fat are the main types contributing to this state. Saturated fats naturally occur in animal products, while trans fats are often created through hydrogenation for texture and shelf life.

Natural Sources in the American Diet

Animal-based foods contribute significantly to solid fat intake in the U.S. diet, including fats from meat, full-fat dairy, and poultry skin. Common examples include butter, cream, cheese (especially full-fat varieties), and meat fats like lard and tallow.

Processed Foods with Added Solid Fats

Solid fats are also added during processing to enhance various food qualities. Artificially hydrogenated vegetable oils are a major source of trans fats in processed foods. Tropical oils like palm and coconut are plant-based but high in saturated fat. Foods with added solid fats include commercially baked goods, fried foods, desserts (like ice cream), snack foods, and refrigerated dough.

Health Implications of High Solid Fat Intake

High consumption of solid fats, particularly saturated and trans fats, is linked to several health issues, especially affecting the heart. Increased intake can elevate LDL ("bad") cholesterol levels, contributing to arterial plaque buildup (atherosclerosis), which raises the risk of heart disease and stroke. Trans fats can also lower HDL ("good") cholesterol. Solid fats are calorie-dense and associated with weight gain and obesity risk.

Solid Fats vs. Healthy Fats

Healthy fats, such as monounsaturated and polyunsaturated fats, are typically liquid at room temperature and offer health benefits. In contrast, solid fats have higher levels of saturated and/or trans fats, which are linked to negative health outcomes. A heart-healthy diet prioritizes replacing solid fats with healthy oils.


Feature	Solid Fats	Healthy (Unsaturated) Fats
State at Room Temperature	Solid or firm	Liquid
Primary Sources	Animal products (butter, lard, meat fat), tropical oils, processed foods	Plant sources (olive oil, avocado), nuts, seeds, and fish
Saturated/Trans Fat Content	High	Low
Chemical Structure	Tightly packed molecules	Molecules with bends or kinks, preventing tight packing
Effect on LDL Cholesterol	Raises "bad" LDL cholesterol	Helps lower "bad" LDL cholesterol
Health Impact	Increased risk of heart disease, stroke, and obesity	Supports heart health, reduces cardiovascular disease risk

Strategies for Reducing Solid Fat Intake

Reducing solid fat intake can be achieved through mindful choices. Simple swaps can improve dietary fat profiles.

Read nutrition labels: Check for saturated fat and "partially hydrogenated oils" (trans fat source).
Choose leaner proteins: Opt for leaner meats or plant-based options.
Select alternative cooking methods: Grill, bake, broil, or steam instead of frying.
Substitute healthy oils: Use olive or canola oil instead of solid fats like butter.
Modify recipes: Use low-fat dairy in place of full-fat versions.

Conclusion

Solid fats, encompassing saturated and trans fats, are widespread in the American diet from animal products and processed items. While fats are essential, excessive solid fat intake negatively impacts health, especially heart health and cholesterol. Many practical steps, from reading labels to simple cooking adjustments, can help decrease solid fat consumption. Replacing unhealthy fats with unsaturated alternatives improves dietary patterns and lowers the risk of chronic diseases.

Heart.org offers more advice on healthy eating

Frequently Asked Questions

Solid fats are fats that are solid at room temperature, including both naturally occurring fats like those in animal products and manufactured fats created through hydrogenation.

While the body needs some fat, excessive consumption of solid fats—especially trans fats and saturated fats—is linked to health problems like heart disease and higher cholesterol. The best approach is moderation and substitution with healthier options.

You can look for saturated fat content on the Nutrition Facts label and check the ingredient list for terms like butter, lard, shortening, palm oil, coconut oil, or partially hydrogenated oils.

The main difference is their state at room temperature. Solid fats are firm due to their chemical structure, which is high in saturated and trans fats. Liquid oils contain mostly unsaturated fats.

Common sources include fatty meats, full-fat dairy products like cheese and butter, baked goods, fried foods, and certain tropical oils such as coconut and palm oil.

Yes, although it comes from a plant, coconut oil is classified as a solid fat because of its high saturated fat content, which makes it solid at room temperature.

To reduce intake, choose lean meat, use healthy liquid oils like olive or canola oil for cooking, opt for low-fat dairy products, and replace processed snacks with fruits, vegetables, or nuts.