Sorry for the late reply - but you are right - you probably dont have enough food in your belly.
The lemon juice in water is a common aid for people with digestion problems. As soon as you wake up have a cup of warm/hot water with the juice of half a lemon. Then wait at least half an hour (especially if brekkie is cereal!)
You didnt say if you were taking the two tablets together which may be a little much for your tummy to handle (especially if you are taking P&B formula at the same time) . Try taking one in the morning and one at night. I need to take a few vitamins and often get an irritated stomache or heart burn so I take half after breakfast and half at dinner and have had no problems since.
I also used to have a banana followed by a piece of dry toast before I took my vitamins as it filled me up and settled my stomache.
One other solution I can think of is taking the Bs after lunch if you dont feel like you can eat any more for breakfast.
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