So this is what being insulin / carb resistant looks like from a Blood Glucose perspective. For those of you who measure BG readings between 3.5 - 4.5 on most days, keep it there... I am a diagnosed Type 2 diabetic who has kept my diabetes under control following the LCHF way of eating. That was partially because the glucophage (metformin) medication impaired my top-end performance on the bike (it severely limits the liver's glycogen capacity under VO2Max conditions) and I wanted to get off the meds. My "usual" fasting BG levels without any meds on LCHF vary between 4.7 - 5.5 My HbA1c (long term BG) level tested a month ago is 5.7. The cut-off for diagnosing diabetes via HbA1c is 6.5, so although I am on the higher side of the scale, I am well within "normal" limits. I have not tested my BG regularly of late, as my diet is boringly stable and does not vary by much. Like I have reported recently, I have however seen an increase in weight and BF since supplementing with whey protein. So following on suggestions from tombeej yesterday, I decided to do a bit of n=1 experimentation, but I cranked the amps up a bit: BG prior to any of the below was 5.7 I consumed 100g of PVM whey protein, mixed with 200ml cream and 100ml milk. 1 hour later my BG was 7.9. Two hours later my BG was still 7.2. I then went out for dinner and had pork belly, but instead of the expected potato gnocchi, it was served on mash & onions. I gobbled that down and decided to really stretch things, so I had half of a chocolate brownie with some ice cream for pudding. 1 hour later, my BG was 9.4 !!! (PS, I felt like death afterwards) My fasting BG this morning was 6.4, so I had my fatshake, which also had about 50g of PVM whey added. 1 hour later, BG was at a massive 10.4 (I am thinking part of the reason for this is a residual effect from yesterday as well as a cumulative dairy + whey effect). Went for an hour's MTB and BG immediately post that was 6.5. My blood ketones this morning was a measly 0.2 - far from being in the fat burning zone. So... I will by a process of elimination establish what my insulin response is to dairy (milk and/or cream) and protein, separate from each other, but for now my money is on the protein as a big cause of the spike. What to do about this ? - probably means I need to either spread the whey consumption out a bit more, or consume it immediately prior to or just after a ride. @Helpmytrap - if you do supplement with protein, it would be interesting to compare notes ? PS. On that reading after the 3 sips of milk, just do another control check to be 100% sure. I have often found my BG being higher than normal after longer, intense rides, and my theory is that it is the liver and pancreas trying to supply energy due to the higher demand, therefore you have higher levels of available BG. But I may be wrong... edit:typo