How can I stop my BMW 316 burning oil?

I have a 1.8-litre 2003 BMW 316ti Compact automatic that has covered 96,000 miles. In the last year and a half it has started to using oil. It is not burning oil, and there is no blue smoke coming from the exhaust, and my local garage has confirmed this. They say it is using it internally and recommend solving the problem using a thicker grade of oil. Is this sound advice?
It is burning it. Only very slightly but otherwise where is it going? Probably via valve stem oil seals. I definitely don't recommend a 'thicker' grade of oil. What might have worked with a clapped out Morris Minor won’t work with a BMW engine.
Answered by Honest John on

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