I often have indigestion when I go out for dinner or drinks with friends, even if I consume less than I do at home. The main difference is that I talk more when I'm out. I become incredibly full, find it difficult to take even a sip of water and my nose starts to run. I feel better only when I lie down. Why is this?
It sounds highly likely that you are an air-swallower. When you socialise, you constantly gulp down small amounts of air – it's a habit that you may not notice yourself – and as the air accumulates, it becomes a large bubble in the top half of your stomach, hence the feeling of fullness. The change when you lie down is due to the fact that the bubble is no longer pushing against the underside of your diaphragm. To counteract this, try to avoid swallowing when you are chatting, or at least to postpone it for some time before you do. We produce saliva constantly, and it has to be swallowed from time to time: you are simply doing it more often than most, and taking in air as you do so. It takes time, but it's a matter of training yourself to do it less frequently.

I've read recently that if you get around eight hours of sleep a night, it leads to a healthier life. I am in my 70s and sleep for around 10 hours – does this mean I may live longer?
It doesn't work like that. All the studies report is that, if you have a reasonable sleep pattern, it may help you live a longer life. Sleeping longer than eight hours isn't likely to be "healthier" than sleeping for exactly eight hours – which few of us actually do. Studies such as these aren't meant to be guides on how to extend our life, but rather pointers, along with many others, to find what is and isn't linked with good health and longevity. Research has shown that short sleep patterns – such as sleeping for five hours or fewer a night, or working shifts that turn night into day – may be detrimental to health, but I do not know of any studies that have concluded definitively that sleeping for longer improves longevity.

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