Chicken soup has a good reputation in this regard.

In my area most people suggest Gatorade or pedialyte (my go to). Going without a meal or a few is okay, but make sure to drink, get electrolytes, and make sure it has sugar in it.

Meal replacement shake (or bar) with calories, vitamins, and minerals. It’s what doctor’s recommended after I hit the pavement.

Hot buttered toast!

Nuts are super nutrient-dense. Just a handful gets you a decent amount of calories & protein. You can crush some up and mix with your oatmeal if they're too much to chew.

BRAT diet. Bananas rice applesauce toast.

Chicken soup, plain white rice, buttered toast, peanut butter, and crackers are all things I can usually tolerate when I feel that way. Sometimes banana or vanilla yogurt. I hope you feel better soon!

Congee / rice porridge. Cook rice way down until it's breaking apart. You can go simple/traditional by cooking it in water with a little ginger, or kick it up a notch by cooking it in chicken broth to add more flavor.

Nuts have a lot of calories in a small package, and as a migraneuse I can also verify that nuts and dried cherries are one of the least offensive things to deal with if you end up puking. If you have miso, miso soup is easy and gentle and tasty.

But mostly make sure you are drinking water with electrolytes. Your body can survive well without food calories for quite some time, and lack of appetite when sick may be a signal to fast and rest. Dehydration is much more likely and much more damaging.

Any soup is good imo. Like Cauliflower soup with bacon and garlic bread. Meat/vegetable soup.

As a last resort drinking broth can work.

It’s about getting energy into your body so you can heal

Disclaimer: English is not my first language and I’m too tired and sick to look them all up

Chicken broth and saltine crackers.

I find greasy umami stuff in small quantities gets me from "hunger nausea" to "hunger"

E.g buttered toast.

Honestly a good smoothie from somewhere is all I can get down when I'm feeling like that. Filling for about an hour or two though but pack with vitamins and goodness.

Instant ramen and crack an egg into the boiling water right at the end and stir. Gives it some protein and makes it a more substantial meal.

Add some good (low sugar and low added fats) peanut butter or any other nut butter and/or ground nuts to your oats. Makes for a healthy and calorie rich meal that keeps you sated for a while. It’s easy on the stomach, does not cause the blood sugar to rise quickly and you can eat it spoon by spoon over the whole day, if necessary.

Also don’t forget to drink plenty. I find tea and highly diluted apple juice (like 10%) are ideal when I am sick.

Oatmeal is my go to! Whenever I land in the hospital due to my Crohn's issues, I end up having a lot of it. It's thick enough to feel full from it, and while it doesn't have the most of nutrients, its better than nothing.

It helps that if you add some flavoring of your choice to it, it doesn't taste bad and thus makes it even better.

Get better soon!

Applesauce

Chicken noodle soup

While you can go for a period without many calories, you will need electrolytes. The recommendations for things like Pedialyte will help with that, but for foods you may just have to try what works for you. It's so personal.

Stay hydrated and "salted" and go from there. If you can't keep it down then it isn't for you. Salty foods will help you retain water.

Soup broth.

Ive had diabetic ketoacidosis a few times. Once it starts coming on you can't eat Anything. For a couple days or more.

Then the treatment is ice chips and IV insulin for a few days.

Coming out of it, your stomach is the size of a walnut and the thought of eating makes you want to make you puke.

My roads back to eating:

Broth from ramen cups. Liquid meal replacements. If you have a soy allergy, take a close look at the ingredients. Miso broth.

Drinkable yogurt.

Bland pasta with just olive oil.

Granola bars.

My experience is that I eventually get hungry again.

Best of luck dealing with your situation.

Edit: per others, chicken soup (I can get the broth down) and Pedialyte or Gatorlyte. Getting dehydrated does not help.

My wife and friends think I am nuts, but when I'm feeling digestively challenged I go for the "burn it out" philosophy. I go to my local tex-mex place and wolf a couple bowls of spicy salsa. Follow up with a chile relleno covered in queso and I'm normally right as rain (after a quick stop in the quiet, tiled room of requirement).

Get some liquid IV powder. It is full of electrolytes and minerals and easy on your stomach. The last time I was in your shoes I did it for two days straight and it kept me going even at work. With that or get some Pedialyte, is not as good in my opinion, but will do similar things for you.

Chicken soup. Easy to make, can add rice and it is super healthy.

Ingredients: One onion, and you don't need to cut it to small pieces. One carrot One or two celery stick Whole raw or roasted chicken.

Through everything on big pot, cover with water, lower the heat when start bubbling.

Let it simmer for 40 to 60 minutes.

Add rice or potatoes or any other vegetables you like.

Can freeze really well for months.

White bread. Bland enough to avoid eating aversions and puts some energy in you. Plus, most people already have some! Not claiming it's healthy, but when I'm sick and the thought of eating makes me want to puke it manages to slip past my radar.

When I have issues eating I go for non-offensive foods that are easy to swallow such as a can of white beans in tomato sauce, plain full fat Greek yoghurt, oatmeal made with milk and not water, lentil soup. I sometimes make 1000 kcalorie smoothies with half an avocado, 2 tbsp peanut butter, cup of 10% fat yogurt, a banana, 1/2 cup oatmeal and enough orange juice to make it liquid. Will not win any taste awards but does contain a bunch of good stuff.

its very easy to dehydrate when youre sick, especially if you have diarrhea. Basically your body trying to flush out whatever is irritating you. Most electrolyte packs from pharmacy have glucose added. Glucose is very easily digested and provides energy source when your DI is not working. Also most doctors recommend to drink coke, since its full of sugar and has acidic pH which is bad for viruses. toasted bread also works, easily digestible and doesnt iritate

Soylent came out about when I was having surgeries for Crohns and I used it at stages where I was healthy enough to bulk. I've been in remission for years but it's still pretty hard to gain weight so I keep Soylents around to pack extra calories in. Use it as a coffee creamer too, surprisingly it froths really well. Also add it to oatmeal.

Also eating complete garbage food is better than nothing, I've made that tradeoff many times. Salt fat and sugar cater to what we naturally crave.

Soup, crackers, nuts.

When nothing at all sounds good but youre in need of protein, try soy milk. It’s cold, smooth and easy to get down.