Yea I stumped on that and it says electrolytes or crappy diet. I tried daily Nuun + extra salt on my food for a few weeks and it didn't go away. It just went away when I started bulking. And my diet is pretty damn clean
Breakfast - 1 cup oats/1 scoop whey, espresso with oat milk
Lunch 1 - 8oz meat + complex carb + vegetable
Snack 1 - fruit (tomatoes for anti inflammatory and kiwi always + a rotation of mango, apple, berries)
Snack 2 - fig bar or protein bar
Lunch 2 - 8oz meat + complex carb + vegetable
Afternoon snack - hardboiled eggs + fruit
Dinner - 8oz meat + complex carb + vegetable
I'll eat carrots or celery if I get hungry in between.