Hi on a regular basis I get small itch red spots on the head of my penis I went to the docs and he said its thrush. I use canesten cream each time they appear and they go the next day. But then a week or so later they reappear what could be causing this. I think thrush has something to do with yeast could it be my diet?

Yes, thrush can be a result of a diet that is high in sugar, carbohydrates and/or starches which cause the pH of the body to become acidic thus creating an environment for yeast to grow. If this is the case, then you need to change your diet to alkaline foods such as fresh vegetables and lots of water. Avoid sweets, soft drinks and breads.
On the other hand, if diet is not your problem, then I would look at your overall health. Thrush can also be the result of a compromised immune system. You may need to repair your body by taking vitamins, minerals, omega 3, 6 and 9 plus some form of anti-oxidants.
By the way, thrush can be passed from one person to another by touch so safe sex is highly recommended whether oral or intercourse.

If you are sexually active it is important that your partner be treated also.