I thought I'd been so sensible. I took a pair of always comfy, well-worn sandals. Yet five minutes out of the Gare du Nord and I was in agony - and that was just with the smell. I also developed blisters on the balls of both feet.
"Summer foot problem" is a terrible thing. Feet swell, harden, split, blister, throb and stink, leaving you aching and friendless.
The feet have more sweat glands per inch than any other part of the body - an impressive quarter of a million producing an average of half a pint a day.
This is a good thing. It keeps everything supple for the 18,000 steps that you will put your tootsies through during the day. But then we score an own goal by keeping our feet closed in for up to 16 hours a day. In hot weather your feet skid around your pathetically fashionable shoes, bringing blisters, smell and pain.
Some sweat more than others. There are three categories. There are normal people, sweaty people and then there is my family. When I was a teenager you could tell who was at home in summer by the level of malodorous waft as you walked through the door. Excessively sweaty feet syndrome is known as hyperhidrosis - I'm so pleased to have a disease.
Donald Lorimer, former chairman of the Council of Chiropodists and Podiatrists, says: "You would never allow your hands to get in the state you leave your feet. Think how many times a day you wash your hands. Yet most people wash their feet only once a day. When sweat isn't allowed to evaporate, the normal bacteria feed on the moisture and change the pH which creates the smell."
Wash feet in warm, soapy water, then dry thoroughly - including between the toes (how many of us still do since parents stopped checking?). Try an anti-bacterial soap. When morning and evening are not enough, you can find me with my feet in the sink at work. It may not look pretty but it makes for a sweeter working environment. Good for flexibility too. Go barefoot as much as possible and wear open-toed sandals. And I may be a vegetarian, but hell, what is animal welfare compared with odour? I wear only leather.
Never wear the same shoes two days in a row. They take more than 24 hours to dry thoroughly. If you can, let shoes dry outside, not festering in the cupboard.
Most socks these days have a Lycra or nylon content and are not 100 per cent cotton, which in hot weather, says Lorimer, "is like putting your feet inside a plastic bag". You wouldn't keep your supper in a plastic bag under the desk all day and expect it to taste good in the evening. So come on, give your feet some respect.
1. They're sensitive soles: sweat glands on the sole of the foot respond mostly to emotion so, on hot days, don't upset yourself or fall in love.
2. Use pumice on hard skin, then E45 cream to soften the skin. You can also use surgical spirit and maybe talc, although Lorimer warns that talc can be abrasive.
3. Camphor oil is good for sweaty feet.
4. Treat feet in hot weather like a teenager. They demand freedom but they still need support. Don't wear shoes with rough edges without socks, or flippy-floppy, unsupportive sandals if you are going to walk any distance.