What fatty foods should you avoid when sick? A comprehensive guide

November 13, 2025 •

4 min read

When you're ill, your digestive system often slows down, making it harder to process complex foods. That's why understanding what fatty foods should you avoid when sick is critical to prevent aggravating symptoms like nausea, indigestion, and bloating, allowing your body to focus on healing.

Quick Summary

Fatty, greasy, and processed foods are difficult to digest and can aggravate symptoms like nausea, stomach pain, and inflammation during illness. Prioritize bland, easy-to-digest alternatives like soups and lean proteins to support your body's recovery.

Key Points

Avoid Greasy and Fried Foods: Deep-fried items like french fries, donuts, and fried chicken are difficult to digest and can worsen nausea and stomach upset.
Steer Clear of Fatty Meats: Heavy, fatty cuts of meat and processed options like bacon and sausages are hard on your digestive system and can promote inflammation.
Limit High-Fat Dairy: Full-fat milk, hard cheeses, and ice cream can be difficult for some people to digest, especially during a stomach illness, causing bloating and nausea.
Opt for Bland Alternatives: Focus on easy-to-digest foods like broths, crackers, toast, and lean proteins to provide nutrition without overwhelming your system.
Stay Hydrated: Focus on drinking plenty of fluids like water, broth, and herbal teas to combat dehydration, which is often a side effect of illness.
Reduce Processed Sugars: Excessive sugar, often found in pastries and baked goods, can increase inflammation and may inhibit immune cell function.

The Negative Impact of High-Fat Foods on Your Body When Sick

When you're battling an illness, your body is working hard to fight off infection, leaving your digestive system less efficient. Consuming high-fat foods during this time can place an unnecessary burden on your gastrointestinal (GI) tract, diverting energy away from your immune system and potentially prolonging your recovery. Fats require more time and digestive enzymes to break down than carbohydrates or proteins, which is why a plate of fried food can feel so heavy when you're feeling unwell.

Slowed Digestion and Increased Discomfort

High-fat foods delay gastric emptying, the process by which food moves from your stomach to your small intestine. This can lead to a feeling of uncomfortable fullness, bloating, and stomach pain. For those with the flu or a stomach virus, this can trigger or worsen nausea and vomiting. In some cases, a high-fat meal can even trigger diarrhea as the digestive system struggles to cope.

Inflammation and Immune Function

Certain types of fats, particularly saturated and trans fats found in many processed foods, can promote inflammation within the body. While some inflammation is a normal part of the immune response, excess or chronic inflammation can put extra stress on your system and may hinder recovery. A diet high in unhealthy fats can also negatively affect your gut microbiome, potentially impairing immune function when you need it most.

Specific Fatty Foods to Avoid When Ill

For a smoother recovery, it's best to steer clear of the following categories of fatty foods:

Greasy and Fried Foods

This is the most obvious and problematic group. Fried chicken, french fries, donuts, and mozzarella sticks are all loaded with oil that is notoriously hard on the digestive system. Even if you don't have an upset stomach, the heavy, oily nature of these foods can leave you feeling sluggish and can aggravate a sore throat.

Fatty Meats and Processed Items

Fatty cuts of meat like bacon, sausage, and rich burgers are high in saturated fat and require more effort to digest. Likewise, processed meats like deli slices and pepperoni are often high in sodium and unhealthy fats, which can cause dehydration and inflammation. Instead of these heavy options, opt for lean, baked, or grilled proteins when you have an appetite.

High-Fat Dairy Products

For some people, especially those with viral gastroenteritis, dairy products containing lactose can be difficult to digest and can lead to bloating and nausea. While the link between dairy and mucus production is largely a myth, the high-fat content of full-fat milk, hard cheeses, and ice cream can still pose a digestive challenge. Plain, non-fat yogurt with live active cultures, however, may be tolerable in small amounts and could even aid gut health.

Pastries and Baked Goods

Items like cakes, cookies, and pastries are often made with a combination of high-fat ingredients, such as butter or shortening, and excessive sugar. This combination can be particularly inflammatory and taxing on your system when you're sick. High sugar intake can also suppress the immune system, making it harder for your body to fight off infection.

What to Eat Instead: The BRAT Diet and Beyond

When you're sick, focus on nourishing, easily digestible foods. The BRAT diet (bananas, rice, applesauce, toast) is a classic for a reason, as these foods are bland and gentle on the stomach. Here is a list of other excellent alternatives:

Clear Fluids and Broths: Chicken soup broth, vegetable broth, and clear sports drinks help with hydration and replace lost electrolytes without taxing the digestive system.
Soft, Bland Foods: Plain potatoes, oatmeal, crackers, and pretzels are easy on the stomach and provide carbohydrates for energy.
Lean Proteins: Baked chicken breast or fish can provide essential nutrients for muscle repair without the heavy fat content.
Ginger: Ginger ale (non-carbonated), ginger tea, or ginger candies can help soothe nausea.
Steamed Vegetables: Lightly steamed carrots or zucchini offer vitamins and minerals in an easily digestible form.

Comparison Table: Foods to Avoid vs. Foods to Embrace


Foods to Avoid (High-Fat, Hard to Digest)	Foods to Embrace (Easy to Digest, Nutritious)
Deep-fried foods (French fries, fried chicken)	Broth-based soups (chicken noodle, vegetable)
Fatty cuts of meat (Sausage, bacon, burgers)	Lean proteins (Baked chicken or fish)
High-fat dairy (Full-fat milk, hard cheese, ice cream)	Plain, non-fat yogurt with live cultures (for some)
Processed snacks (Chips, cookies, pastries)	Bland starches (Crackers, toast, rice)
Rich, creamy sauces and dressings	Mild, fresh sauces or light seasoning

Conclusion

While a craving for comfort food when sick is natural, it's important to be mindful of your body's limitations during recovery. High-fat foods put added strain on your digestive system, leading to discomfort and potentially extending your illness. By prioritizing bland, easily digestible, and hydrating options, you can give your body the best chance to recover quickly. Listen to your body and stick to simpler foods until you're feeling back to normal. For more information on maintaining good digestive health, consult resources from trusted organizations like the National Health Service (NHS).

Frequently Asked Questions

When you are sick, your digestive system works more slowly, and your body focuses its energy on fighting the infection. Fat requires more time and digestive enzymes to break down compared to carbohydrates and protein, so consuming it places an extra burden on your weakened system.

Yes, greasy and fatty foods are a common trigger for worsening nausea and indigestion, especially when you are already feeling queasy. They delay stomach emptying and can lead to a feeling of heaviness and discomfort.

High-fat dairy products can be hard to digest. While the link between milk and excess mucus is debated, the high-fat content itself can cause discomfort, bloating, and nausea for those with a sensitive stomach.

It is generally best to avoid all heavy, high-fat foods when ill. However, you can reintroduce healthy fats from sources like avocados and fatty fish in moderation as you recover and your appetite returns. Initially, stick to the blander foods.

Yes. While colds are different from stomach bugs, fatty foods can increase inflammation and make your body produce more mucus for some individuals, which can worsen symptoms like congestion. It's best to stick to easy-to-digest, anti-inflammatory foods.

Lean, non-fatty cuts of meat like baked or grilled chicken breast or fish are best. They provide protein to help your body heal without the heavy fat content found in red meat or processed meats.

Opt for gentle cooking methods like baking, boiling, steaming, or grilling. Avoid frying, sautéing in excessive oil, or adding heavy, creamy sauces, which add extra fat that can be hard to digest.