Why you lose your sense of smell and taste when you’ve got a cold
What sucks with both colds and flu (aside from feeling ghastly) is that you can’t even enjoy the flavour of that yummy chicken soup you thought would make you feel better. Of course, it’s because you’ve lost your sense of taste along with your sense of humour.  But ever wondered why you can’t taste properly with a cold or stuffy nose?
First question that needs answering is why a cold causes a stuffy nose in the first place. White blood cells in your body produce chemicals to kill virus-infected cells. This causes increased mucous secretions as well as nasal swelling and inflammation.’
More importantly though, is to understand that the flavour of food involves both smell and taste. In fact, 80% of our taste is related to smell, so it’s not surprising that most of the flavour of a food comes from your ability to smell it. Tongue is your taste organ, as it can sense salty, sweet, sour, bitter and umami (savoury). Our sense of smell (known as olfaction) provides the rest of a food’s flavour, which is why it’s difficult to appreciate food flavour when you have nasal obstruction from a cold, stuffy nose or rhinosinusitus. A small area called the olfactory cleft high up in the roof of your nose senses smell. Here, special cells sense different odours found in the air that we breathe and then send signals to the brain via the olfactory nerve. Anything that interrupts taste sensations being transmitted to the brain will cause taste problems.
When you have a cold, the swelling causes inflammation and obstruction, which impairs your smell. The flavour of food is produced only after taste is combined with a smell, so if a stuffy nose impairs your sense of smell, it will also decrease your perception of taste.

When your nose is stuffy, taste receptors in your taste buds have to do the job of assessing food flavour in different taste molecules all on their own. Truth is, even though you have around 2000 and 5000 taste buds on your tongue, in your mouth and throat (with each containing 50 to 100 taste receptor cells) they still don’t come close to what your nose knows! The two smell (olfactory) receptors found high up in your nasal passages have up to six million cells and can sniff out differences of at least one trillion odours.

We know that losing your sense of taste when you have a cold can make you feel miserable, but don’t worry, it usually doesn’t last long.  your normal taste should return when the infection passes.😊
Source: internet