Lack of sense of smell can bring about malnutrition warn experts

Image courtesy Robin Higgins/Pixabay

A recently completed peer-reviewed research has brought attention to the worrying dietary complications for people experiencing altered smell and taste.

People who are experiencing a loss of their sense of smell are at a higher risk of suffering from serious diet and nutritional issues such as malnutrition, new independent research shows.

Extreme cases are linked to Parosmia. Parosmia can occur following an initial episode of anosmia (smell loss) although can follow different paths in some people. 

People with parosmia can experience a distorted sense of smell where previously neutral or even pleasant smells including everyday scents and food items can, instead, sell disgusting. 

For example items like onion, coffee and garlic scents are common triggers and can smell like raw sewage or vomit. 

Researchers reached the conclusion that “the ways in which ‘smell loss symptoms’ are currently framed in the literature don't accurately present the extent of potential dietary complications in terms of nutritional compromise, weight loss and weight gain...”

Dr Duika Burges Watson of Newcastle University is the lead author on the research. She said: “Some people struggle with malnutrition as a result and they are getting little understanding or support. We’ve been led to believe impacts of smell loss are mild, or a trivial inconvenience but this is far from the experience of those people who are experiencing malnutrition as a result of the loss of the sense of smell."

Chrissi Kelly, who is the founder, AbScent, said; “We have a concern for individuals who might  already already have acute nutritional issues for instance, pregnant women who are victims of morning sickness, people who have existing eating disorders, or those who need to follow certain specific diets such as following specific diets, for example vegans, or coeliacs), or people who are undergoing medical treatment and young people.”

The research has been published in the peer-reviewed journal PloS One with AbScent’s Covid-19 Smell and Taste Loss moderated Facebook support group forum, which had 9,000 members at the time of research. Key findings in relation to nutrition include:

• Smell loss has a major impact on appetite, enjoyment, fullness and satiety. One person said, “All food tastes/smells too disgusting to eat. Only yoghurt is ok. So, I lose weight instead of gaining it.”

• Food became bland and unappetising resulting in a reduced desire to eat, cook or participate in food related activities.

• Parosmia and phantosmia had even more harrowing effects on food and eating

• People with parosmia tend to remove themselves from social and familial meal occasions. Where a partner cooks a meal, this can be revolting to a person who has parosmia. Likewise socialising with friends in pubs, cafes, restaurants or coffee bars can also, literally, make people feel physically sick

• Unpleasant smells are constant and can fluctuate, one person reports, “burning sort of taste and smell’ then, later that month, an ‘awful metallic taste’”

• Healthcare professionals often focus on the olfactory detection of immediate danger (e.g., smoke etc)

• Some people lose appetite, so are therefore unable to eat and undergo weight loss

• Some people may unexpectedly gain weight as they eat more as they attempt  to recapture lost food satisfaction

• People struggled with overwhelming and often pervasively unpleasant parosmic smells. ‘They were described with words that included: sewer, cat food, spicy, pungent, strong herbs, sickly metallic, dirty fish tank, off milk or yoghurt, sweet and grassy, dog food, curry, garlic, sickly sweet metallic, kippers, chemicals and fruity sewage.’

• People alter their cooking, for instance, “I’m trying to focus on other aspects of the ingesting experience like temperature and texture. I am relying a lot on the comforting aspect of soup, the surprising aspects of salads and crunchy snacks.”

• After a period of time people can make adjustments; “I’ve adjusted to foods I can eat and can’t eat now. Some things I just ploughed through and tried to get used to the adjusted taste. Some things still make me feel sick, like washing up liquid and perfume, but most things I find that I can cope with.”

Professor Barry Smith, who is the Director of the Centre for the Study of the Senses at the University of London said; “When it comes to eating, it’s flavour first. We know what we should eat for better health and nutrition, but it’s how the food tastes that encourages us to eat it. 

"Foods lack flavour for those with anosmia, and for people with parosmia many familiar foods taste distorted and disgusting, which means the range of acceptable and nutritious food can be drastically reduced.”

AbScent is a charity registered in England and Wales since 2019 and has created an unrivalled resource of trusted information supported by a distinguished advisory board and working with the latest scientific and clinical evidence. AbScent advocates to increase understanding and raise awareness of the conditions and their impacts supporting research into smell conditions.

For help please visit AbScent’s website https://abscent.org. 

(NOTE: My wife caught COVID 19 a year ago and her sense of taste and smell has still not returned to normal.)