When looking for someone to help you with anything to do with dieting or health - whether you want to eat more healthily or to lose weight or to know what will be safe during pregnancy, for whatever reason - it is important to remember to consider the credentials of those offering you advice. Although this is something to consider anyway, it is particularly important in terms of your health.
A quick way of establishing whether or not someone's word can be trusted is to see how they title themselves.
'Dietitian' is a legally protected term. You can only claim to be a dietitian if you have the qualifications to prove that you are capable of commenting on such matters. 'Nutritionist' is not; anyone can call themselves a nutritionist and offer people advice without having done any research or having any evidence to back up their claims.
When seeking health advice, a dietitian is a professional. A nutritionist is a modern-day quack and, although their advice may well be sound, it would be best to take it cautiously.