When sick, is it better to eat or not? The truth about nutrition and illness

October 13, 2025 •

4 min read

The old adage, 'feed a cold, starve a fever,' is largely debunked by modern medical science. So, when sick, is it better to eat or not? The answer depends on your symptoms, but your body always needs some form of fuel to fight infection and recover.

Quick Summary

Your body requires energy and nutrients to fuel your immune response when ill, making it important to eat and stay hydrated. Small, frequent meals of easily digestible, nutrient-dense foods are recommended, while focusing on hydration is key, especially if you lack an appetite.

Key Points

Debunk the Myth: The adage 'feed a cold, starve a fever' is medically inaccurate; your body needs energy to fight both a cold and a fever.
Prioritize Hydration: Staying well-hydrated is the most critical aspect of recovering from illness, especially with fever, vomiting, or diarrhea.
Listen to Your Body: Don't force yourself to eat if you have no appetite, but do focus on nutrient-rich liquids like broths, tea, or smoothies.
Opt for Nutrient-Dense, Bland Foods: When eating, choose easily digestible foods like soups, broths, and the BRAT diet, while focusing on nutrient-dense options like citrus fruits and leafy greens when possible.
Avoid Inflammatory Foods: Steer clear of alcohol, excess sugar, greasy, and spicy foods, as they can hinder your immune system and irritate your stomach.
Graze, Don't Gorge: If your appetite is low, eat smaller, more frequent meals and snacks instead of trying to consume large portions.

Debunking the “Starve a Fever” Myth

For centuries, people have followed the folk wisdom of “feed a cold, starve a fever,” but modern medicine has revealed this advice to be misleading. The idea stemmed from outdated beliefs that eating would increase body heat, which should be avoided during a fever, and that fasting would help cool the body down. In reality, a fever increases your body's metabolic rate, meaning you burn more calories to fight the infection. Restricting food intake during this time can be counterproductive, as your body is in high demand for fuel. A cold or fever is the result of your immune system working hard, and that work requires energy and key nutrients.

Why Your Body Needs Fuel During Illness

When you are sick, your immune system is in a state of heightened activity, mobilizing immune cells to locate and destroy pathogens. This intense process requires a significant amount of energy, and without it, your body's ability to fight off the illness can be compromised. Furthermore, illness, especially when it involves fever, can increase your body's need for specific nutrients. For example, some nutrients may be poorly absorbed by the gut during an infection, or the body may use them up faster than usual. Eating a nutrient-dense diet provides the vitamins, minerals, and calories necessary to power this recovery effort. Protein, in particular, is vital for building and repairing tissues and producing antibodies.

The Golden Rule: Prioritize Hydration

Regardless of your appetite, hydration is the most critical element of recovery. Fever, vomiting, and diarrhea can lead to rapid fluid and electrolyte loss, increasing the risk of dehydration. Staying properly hydrated helps regulate body temperature, aids in flushing out toxins, and transports nutrients to cells.

Good sources of hydration include:

Water: The most fundamental source of hydration.
Broths and Soups: Warm liquids can soothe a sore throat and help relieve congestion. They also provide fluids and electrolytes.
Herbal Tea: Varieties like ginger or peppermint can help with nausea, while chamomile can be calming.
Coconut Water: A natural source of electrolytes like potassium and sodium.
Low-Sugar Electrolyte Drinks: Replenishes vital minerals lost through sweating.

Best Foods to Eat When Sick (and What to Avoid)

Foods to embrace

Chicken Soup: A classic for a reason. It's hydrating, anti-inflammatory, and the cysteine from the chicken can help thin mucus.
Yogurt with Live Cultures: The probiotics can support a healthy gut and boost immune function.
Ginger: Known for its anti-nausea effects, it can be consumed in tea or incorporated into food.
Garlic: Contains compounds with antibacterial and antiviral properties that may support the immune system.
Fruits High in Vitamin C: Citrus fruits, berries, and kiwi are rich in this antioxidant, which supports immune cell function.
Bland Foods: For stomach bugs, the BRAT diet (bananas, rice, applesauce, toast) is easy to digest. Oatmeal is another bland, nutrient-dense option.
Lean Protein: If your appetite allows, lean protein from poultry, fish, or eggs provides essential building blocks for recovery.

Foods to avoid

Sugary Foods and Drinks: Excess refined sugar can promote inflammation, which may hinder recovery.
Spicy and Greasy Foods: Can upset an already sensitive stomach and increase inflammation.
Alcohol and Caffeine: Both are diuretics and can worsen dehydration, hindering the immune response.
Hard or Crunchy Foods: Can irritate a sore throat and be difficult to swallow.

Eating Strategies for Different Symptoms

It's important to listen to your body and adjust your eating habits based on your specific symptoms. If you have a sore throat, stick to soft, warm foods like soups, oatmeal, and scrambled eggs. If nausea or an upset stomach is the main issue, bland, easy-to-digest foods are your best bet. When your appetite is low, try grazing on small, frequent snacks rather than forcing yourself to eat three large meals. Nourishing liquids like smoothies or protein shakes can also be a good way to get calories and nutrients without feeling overwhelmed by solid food.

Comparison of Foods for Different Ailments


Symptom	Recommended Foods	What to Avoid	Why It Works	Citations
Cold/Flu	Chicken soup, citrus fruits, garlic, ginger, herbal tea, yogurt	Alcohol, sugary foods, high-fat foods	Hydrates, soothes throat, provides anti-inflammatory and immune-supporting nutrients
Stomach Bug	BRAT diet (bananas, rice, applesauce, toast), clear broths, ginger tea	Spicy foods, greasy foods, dairy (temporarily)	Bland foods are easy on the stomach, while hydration and electrolytes are key to recovery
Sore Throat	Warm broth, hot tea with honey, cool foods like ice cream or yogurt, soft foods	Hard or crunchy foods, highly acidic fruits like oranges	Soothes inflammation and irritation, providing comfort and hydration
Fever	Hydrating fluids, broths, electrolyte drinks, fruits, lean protein	Alcohol, processed sugar	Replenishes calories and fluids burned by the body's increased metabolic rate

The Recovery Phase: Rebuilding Your Strength

Once you begin to feel better and your appetite returns, it's crucial to continue supporting your body with good nutrition to fully recover and rebuild strength. Eating a varied diet with a balance of macronutrients and micronutrients helps restore any depleted reserves. Focus on high-quality protein to repair muscles and tissues, and reintroduce a full spectrum of fruits and vegetables to get a boost of vitamins and antioxidants. Don't forget to maintain your hydration levels as you return to normal activity.

Conclusion

In short, the choice is not whether to eat or not, but rather how to eat smartly and effectively to support your body's fight against illness. Abandon the outdated notion of starving a fever and instead focus on providing your body with the nutrients and fluids it needs to heal. Prioritizing hydration is key, especially when dealing with fever or digestive issues. For a low appetite, focus on small, frequent meals of easily digestible foods like broth, soup, and simple carbohydrates. By listening to your body and making wise nutritional choices, you can provide your immune system with the best possible chance for a speedy and complete recovery. For more information on illness prevention and recovery, you can consult resources like the Centers for Disease Control and Prevention.

Frequently Asked Questions

Yes, it is better to eat when you have a fever. A fever increases your body's metabolic rate, requiring more calories and energy to fight the infection. While a loss of appetite is common, consuming nutrient-dense foods in small, frequent amounts is beneficial.

The best foods to eat when sick include hydrating liquids like chicken soup and broth, easy-to-digest options like bananas and rice, and nutrient-rich sources like citrus fruits, yogurt, ginger, and garlic. These provide energy, fluids, and immune-supporting compounds.

When sick, you should avoid alcohol, excessive refined sugar, greasy foods, and spicy foods. These can lead to dehydration, increase inflammation, or irritate a sensitive stomach, potentially slowing your recovery.

No, you do not need to force yourself to eat if you have no appetite. The priority is staying hydrated with fluids like water, herbal tea, or broths. If you can tolerate it, try small, frequent snacks to provide some energy, but listen to your body.

A loss of appetite during illness is a natural bodily response. During an infection, the immune system releases chemicals that can affect your brain and cause a feeling of fullness. It can also be your body's way of conserving energy that would otherwise be used for digestion.

Hydration is extremely important when ill, especially if you have a fever, vomiting, or diarrhea. It is necessary for regulating body temperature, transporting nutrients, and flushing out waste products. Dehydration can hinder your body's healing process.

The BRAT diet consists of bananas, rice, applesauce, and toast. It is recommended for stomach-related illnesses because these foods are bland, low in fiber, and easy to digest, which can help settle an upset stomach and firm up stools.