Fruits are considered to be one of the best sources of nutrients. It is rich in fiber and antioxidants. Each fruit has different nutrients. But few fruits are not advisable to have when you are sick as they may prolong your recovery.
Allergy symptoms are triggered in our body when a chemical called Histamine is released. These are found in some of the food we eat. Some fruits are considered to be histamine liberators though they are not high in histamine content. But these fruits if had when we are ill trigger cells to release histamine and activate an inflammatory response. And this response may increase congestion, fatigue and other symptoms of flu or cold. Some of the fruits that has to be avoided when you are not well:

Citrus Fruits
Though citrus fruits are considered to be a vital food with nutrients essential for cold and flu resistance it is not advisable to take it when you are sick. The acidity levels found in oranges and grapefruit may further irritate the throat though the vitamin C enriches your body. So try another souces of vitamin C till you recover.

Strawberry which is said to be a super food are histamine releasers, which may result in congestion. Histamine-powered mucus can create a sense of discomfort in your nose and sinus area, so avoid strawberries until you are feeling better.

There are many varieties of banana each with different and enormous nutrients, but it is best to enjoy them when you are healthy. This fruit can trigger a histamine release, thus need to avoid when you are sick. Bananas have a high sugar content, which may lead to inflammation and decrease the efficiency of your immune system’s response to disease. But you can definitely add bananas to your diet once you recover.

Papaya a tropical fruit which has a high potent of histamine-releasing powers, that may make some of your most irritating cold symptoms worse. Histamine has the ability to make your nasal passages swell, leading to feelings of congestion and stuffiness. So avoid slicing up papaya until your sinuses are clear and you feel congestion-free.

Pineapple is another tropical food, best to avoiding until you have fully recovered. This fruit has high levels of histamine, which can prolong your cold and flu. Additionally, pineapple contains ascorbic acid, which may irritate sore or scratchy throats.

Do not have avacado till your sinuses clear! This fleshy, fat rich fruit has histamines, which means consuming avocado could make your runny nose even worse. Because of its higher fat content it may be difficult to digest during illness.

Avoid dates, especially the dried dates, when you are sick. Dried dates contain a high level of histamine due to the preservation process. Dates also have one of the highest sugar contents of all fruits, so consuming it may prolong your infection. Sugar causes inflammation which weakens your body’s white blood cells and resulting you to be more susceptible to illness.

Figs are one of the best way of adding extra vitamins and minerals to your diet, but when you are not well it’s better to avoid them. Dried figs, in particular, contain high levels of histamine, resulting in the increase of some of your most irritating cold symptoms such as a runny nose or a headache.