I will try to explain this precisely in the style of a geometric proof so people can contest specific points im making rather than debating in a disorganized manner.
1.vegetables and most fruit alkalize the gut
2. animal products acidify the gut.
3. a personal with an alkaline gut will crave more fruits and vegetables while a person with an acidic gut will crave animal products.
4. Whether your body tells you that you want animal products at the moment or plant products at the moment is more determined by the ph of your gut than whatever nutritional need your body may have elsewhere at the time.
5. Since the ph of your gut determines what you are craving at the time more than anything else and the PH of your gut is determined by what you have been previously eating this means that your percieved instincts are based more on what you previously ate than an actual nutritional need your body experiencing at the time.
THerefore simply following your percieved instinct above all else is not an accurate way of determining your bodies current nutritional needs since itis greatly affected by what you have eaten immediately preceding.
I would wager instinctive eating only works with fully RAW and UNCONDIMENTED.
Anything cooked and condimented throws off the instinct.
At the same time it would be dangerous and ludicrous to say we should be ignoring instinct.
In my experience with healing people... I solicit from the patient / pregnant woman their INSTINCT, their CRAVINGS... which by my experience should be given the first shot even over ruling sometimes the healer's first guesses. Hands on experience on that patient should over rule any "theory".
Pregnant women not being able to satisfy their cravings can and do lose their babies... must be lack of nutrition or something.
My healing experiences and personal rpd experience disagrees with this alkaline gut theory.
For my personal experience, it is my instincts that control the quantity of animal food I consume over the days, weeks and months. Year 2 and 3 meat consumption at 500 to 600 grams per day vs declining year 4 and 5 to todays less than 200 grams per day is to my knowledge something instinctive that my body tells me.
And might I add, I follow the fruit seasons in my country... so at the same time I am forced by the availability or unavailability of certain fruits.