Upset stomach and headache

I’m not sure if I’m the only one having this problem but I have tried Huel Black vanilla for the past five days. My boyfriend has been using huel for over a year and I thought I’d try it. He swears by the new huel black. He made me my first drink in a blender and I felt fine but when I made my own drink with two scoops and 18oz of water in the shaker for 30 secs after having huel my stomach Immediately hurts and it will hurt for at least 10 hours after I consume it. I had Huel only for lunch and ate my other meals. I had it 5 days in arrow and on the 5th day I only had one scoop with water blended and still had super bad stomach pain and got a headache.

possible allergy or intolerance to ingredients and or underlying gut health problems, or mixed with something else you consumed it caused this effect.

If you’re not used to the high fiber content then that could explain your issues. As fiber acts like a sponge try drinking more water throughout the day.