There’s no evidence that any one specific diet can treat lung cancer. However, eating healthy may help enhance your overall health, improve energy levels, and give you more strength during treatment.

Cancer and its treatment can sometimes negatively affect your appetite, making it difficult to eat a balanced diet.

In severe cases, this may lead to cachexia, a condition associated with severe weight loss and muscle wasting that can worsen your outlook.

It’s a good idea to speak with your doctor or a dietitian to help you create a balanced eating plan that will help you maintain your weight and health during your treatment.

The broad goal of any lung cancer diet is to help slow down disease progression.

In addition, if you have lung cancer, you should generally try to maintain a moderate weight and eat a balanced diet while avoiding any foods that may worsen treatment side effects such as diarrhea or mouth sores.

What this looks like in terms of diet may vary from person to person. Some people may need to eat enough calories to avoid losing weight, while others may need to lose some weight safely.

Your doctor can help tailor a diet to your needs and food preferences. These may include:

Mediterranean diet

The Mediterranean diet primarily consists of eating the following foods:

  • fruits
  • vegetables
  • cereals
  • legumes
  • nuts
  • seeds
  • poultry
  • certain fish
  • eggs

It also allows for some dairy and wine in moderation, as well as small amounts of red meat.

A 2022 research review has linked eating these foods with a lower chance of developing various diseases, including cancer, and a lower mortality rate. This is because many of these foods contain antioxidants that can help reduce oxidative stress.

Plant-based diets

The Mediterranean diet is heavily focused on plant-based foods.

A 2020 literature review suggests that eating a plant-focused diet, such as a vegetarian or vegan diet, might also help reduce negative cancer outcomes. Still, experts note that more research may be needed to confirm this.

Ketogenic (keto) diet

This is a very low carb, high fat diet. Some research suggests that the keto diet might have an antitumor effect. However, more research is needed to verify whether this diet is actually beneficial for specific cancers.

A 2017 study also shows that this diet may be more difficult to follow while undergoing treatment, so speak with your doctor to determine whether it’s right for you.

Food is essential to good health. Whenever possible, it’s important to choose nourishing foods to help energize your body and keep you strong. This can help you tolerate treatment better, promote your overall well-being, and help you avoid cachexia.

This means eating the right amount of protein and calories, which can help support your healing, boost your immunity, and maintain your energy levels.

Specifically, experts recommend increasing your protein intake to about 1.2 to 1.5 grams per kilogram per day (g/kg/day) to help support healthy muscle mass.

If you’re struggling to consume enough calories, consult your medical team for advice.

Smoking causes about 80% of lung cancer deaths. But there’s also evidence that diet plays some role in lung cancer risk, especially in smokers.

For example, replacing red meat and other foods high in saturated fat with unsaturated fat sources like olive oil, nuts, and avocados may help lower lung cancer risk, especially in people who smoke.

Fruits and vegetables are also an important addition to an anticancer diet, especially in smokers.

In addition, maintaining a moderate body weight and being physically active throughout life may help prevent cancer.

Research also suggests that having high levels of vitamin D in your blood may help protect against lung cancer and improve the outlook of those with the condition.

Your body makes vitamin D from sunlight. Vitamin D is present in foods like fatty fish, milk, and mushrooms. Many manufacturers add vitamin D to certain fortified foods. However, supplementation may be necessary if you have low vitamin D levels.

Speak with your healthcare professional about whether checking your vitamin D levels is right for you.

Eating certain foods and avoiding others may help reduce certain chemotherapy-related side effects.

Chemotherapy drugs are strong medications that kill cancer cells throughout your body. Because these medications are so potent, they can cause side effects.

Every person has different needs, so it’s important to work with your healthcare team to come up with a plan that works for you. Here are some general tips on how to use diet to manage these side effects.

Nausea

  • Eat bland foods such as toast, crackers, and rice.
  • Have smaller, more frequent meals instead of large meals.
  • Eating cold or room-temperature foods may help when you’re feeling sick.

Vomiting

  • Avoid drinking or eating until you are no longer vomiting.
  • Then, only drink small amounts of clear liquids.
  • If you are not continuing to vomit, progress to thicker liquids, such as strained soups.
  • Once you can eat solid foods, try to eat five or six small meals daily instead of three larger meals.

Diarrhea

If you’re experiencing diarrhea, it’s a good idea to avoid the following foods:

  • fatty or fried foods
  • raw vegetables and vegetables with a lot of fiber, like broccoli or cabbage
  • fruit seeds and skins

Instead, focus on eating things like yogurt and cottage cheese, as well as rice, noodles, and potatoes.

You can also try farina or cream of wheat, boiled eggs, smooth peanut butter, white bread, and canned or cooked fruits and vegetables.

For protein choices, opt for skinless chicken or turkey, lean beef, or broiled or baked fish instead of fried options.

Constipation

To reduce constipation, stay hydrated by drinking at least eight big glasses of water each day. Avoid foods and drinks that cause gas, such as broccoli, cabbage, and carbonated beverages.

Instead, try to eat high fiber foods that may help relieve the symptoms. These include:

  • whole grain breads and cereals
  • dried fruits
  • wheat bran or germ
  • fresh fruits and vegetables (with the skin on potatoes)
  • dried beans and peas
  • oats
  • barley
  • brown rice

Before making any dietary changes, speak with your doctor to make sure these foods are right for you.

Lack of appetite

When you don’t feel like eating while undergoing cancer treatment, it’s still important to get the nutrients your body needs. Consult with your doctor and try the following strategies:

  • Eat more frequent small meals and snacks throughout the day instead of three large meals.
  • Increase the amount of high calorie, high protein foods in your diet, like peanut butter, chicken, hard-boiled eggs, and hummus.
  • Drink a nutritional supplement like a protein shake that’s high in nutrients.

Taste changes

When dealing with taste changes, try to experiment with spices and sauces, or try marinating meats for more flavor. Also, pair meats with something sweet and tangy, like cranberry sauce or lemon drops.

Use plastic utensils and cover foods to avoid feeling a metallic taste. In consultation with your doctor, you can indulge in some favorite foods when possible and experiment with new recipes.

In addition, try to chew your food longer and use a straw while drinking. Lastly, it may also help to maintain good dental hygiene with regular brushing and dental checkups.

Mouth sores

  • Ask your doctor if you can take medication before you eat to relieve mouth pain.
  • Eat soft foods such as oatmeal and applesauce.
  • Try sucking on ice pops, frozen yogurt, or ice chip to help numb the area.
  • Avoid foods that are spicy or salty.
  • Don’t eat anything acidic, such as oranges, lemons, or tomatoes.

Learn more: 7 tips for taking care of yourself during lung cancer treatment.

What is the best treatment for lung cancer?

Your first-line treatment will depend on the type of lung cancer you have and its stage. Generally speaking, your treatment is likely to include radiation, chemotherapy, certain targeted medications, and surgery.

Can you live 20 years after lung cancer?

Your outlook also depends on your type of cancer and its degree of progression. That said, a recent study looking at whether early cancer screening can affect survival rates found that 80% of the 1,257 people studied survived for 20 years after receiving a diagnosis of first primary lung cancer.

Nutrition is an important part of lung cancer treatment. The cancer itself and its treatment side effects can reduce your appetite, making it harder for you to get the calories and nutrients you need.

If you’re not eating well and losing weight, talk with your doctor. A dietitian can help you fill in the gaps in your diet.

Adding more nutrient-dense and calorie-rich foods can help you keep up your strength and feel better during your treatment.