Scaling up culinary recipes does not always follow a linear relationship, especially when using spices, salt or alcohol.

For example, for 1 litre of water you might be accustomed to adding 1 measure of salt, but for 4 litres you wouldn't add 4 measures of salt, but much less.

Does anyone know what the explanation for this is?

Cathy Fisch, Orsay, France

Since my 20s, I have drunk on average a bottle of wine a day. I'm now 57. That's 49 UK alcohol units a week. The UK's recommended weekly limit for a man is 28 units.

I recently had a complete health check at my local clinic, and I'm in perfect health. Specifically, my liver function tests are entirely normal. Am I exceptional or are the government limits spurious?

I rarely drink spirits and occasionally substitute beer for wine. I play football and squash. I walk 3 kilometres to and from work. I lead a normal life and, probably due to regular consumption, I never feel drunk, but presumably I am considered a binge or problem drinker.

I don't want advice from a government minister or associated medic. I want objective information. Am I just lucky? Or is my consumption relatively harmless? What's the truth?

David Hunte, London, UK

A UK unit is 10 millilitres (8 grams) of alcohol - Ed

I know people who insist that certain types of alcoholic drinks put them in specific moods when drunk - such as emotional, violent or confident.

Is there any scientific reason why different beverages can have specific effects on mood?

Frederick Allen, Oxford, UK