Doctor reveals reason some people smell bad

There are three main culprits when it comes to body odour – and there’s a big reason some people smell worse than others.

Doctor reveals reason some people smell bad. Picture: iStock

Welcome to Ask Doctor Zac, a weekly column from news.com.au. This week, Dr Zac Turner explains why some people stink more than others.

QUESTION: Hi Dr Zac, last night my Uber driver stunk like a packet of cigarettes. It got me thinking. Why do some people’s skin smell and how is it affected by what you eat and consume? Is there anything we should be doing to prevent this? What are the worst foods for making your skin stink? – Alison, Canberra

ANSWER: Yet another reason to quit smoking: it makes you stink! The smell you encountered from your Uber driver is from the 7000 chemicals present in cigarette smoke. These chemicals cling to your skin, clothing and hair. The chemicals are absorbed into the bloodstream and then excreted through sweat glands and pores, giving off the foul odour.

There are 7000 chemicals present in cigarette smoke and they cling to your skin, clothing and hair. Picture: iStock

Body odour in general is influenced by various physiological and lifestyle factors.

Variations in genes related to sweat production, hormonal changes and medications can play a part in your skin giving off a funk. The three main culprits are typically smoking, diet and lack of hydration. So let’s unpack the two we haven’t discussed.

The foods we consume can influence body odour through the metabolic by-products produced during digestion and metabolism. Certain foods, such as garlic, onions, spices and foods high in sulphur-containing compounds, can impart distinct odours to bodily secretions.

Foods such as garlic, onions, spices and foods high in sulphur-containing compounds can impart distinct odours to bodily secretions. Picture: iStock

Consumption of red meat can affect body odour due to the presence of certain amino acids, such as carnitine and creatine, which are metabolised into volatile compounds like triethylamine (TMA).

TMA has a strong fishy odour and can be excreted through sweat and breath, particularly in individuals with a genetic condition called trimethylaminuria (TMAU).

Alcohol consumption can influence body odour through several mechanisms. Alcohol is metabolised in the liver, leading to the production of acetaldehyde, a highly reactive compound that can be excreted through sweat and breath, contributing to unpleasant odours. Furthermore, alcohol consumption can lead to dehydration, altering the composition of sweat and exacerbating body odour.

Alcohol consumption can influence body odour through several mechanisms. Picture: iStock

Caffeine, found in coffee, tea and other beverages, can also impact body odour. As a diuretic, caffeine increases urine output, potentially leading to dehydration, which can concentrate odorous compounds in sweat.

Maintaining proper hydration is crucial for regulating body odour, as adequate water intake supports the efficient elimination of toxins through urine and sweat. Hydrated skin is less prone to harbouring odour-causing bacteria, thereby reducing the intensity of body odour.

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Dr Zac Turner has a Bachelor of Medicine and Bachelor of Surgery from the University of Sydney. He is both a medical practitioner and a co-owner of telehealth service, Concierge Doctors. He was also a registered nurse and is a qualified and experienced biomedical scientist along with being a PhD Candidate in Biomedical Engineering.