What do you mean if they will let you? Are you sick? And by McDougall meals are you following a plan/cook book, or you mean you only eat pre-prepared meals? The only forseeable problem would be that your dietician isn't well versed in vegan diets, and you should look for a vegan nutritionist, they exist. Or if you are on some medications, you shouldn't eat low salt. I actually have to have some salt in my diet.
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