How else does he think we deal with excess protein, if we go a little over our daily requirement? It is broken down and recycled so nothing is wasted. Happens every day. Unless we eat too little protein...
That’s the only argument he has, but you raise an excellent point with your last sentence.
The average person on this forum can survive without carbohydrates in their diet. However, people like me with very high activity levels need either a moderate carb intake or a high protein intake to replenish our glycogen reserves (and without our own muscle breaking down).
Consequently, most people on this forum have success with LCHF diets. However, someone like me needs a LCHFHP (Low Carb/High Fat/High Protein) approach or a MCHFMP (Moderate Carb/High Fat/Moderate Protein) in order to replenish their glycogen.
This is an excellent article that addresses a number of different topics we discuss on this form:
“How Many Carbohydrates Do You Need?”
http://www.bodyrecomposition.com/nutrition/how-many-carbohydrates-do-you-need.html/
The carbohydrate table perfectly explains my situation and why I can eat as much as 250g of protein/day yet remain in ketosis.
The article discusses the relationship between LCHF diets and people with insulin resistance, but also why a LCHF diet may not work well for someone without insulin resistance.
That article alludes to a second article titled “Insulin Sensitivity and Fat Loss” which I think is also an excellent read for most members on this forum:
http://www.bodyrecomposition.com/fat-loss/insulin-sensitivity-and-fat-loss.html/
Bottom line: the guy you conversed with has a point. However, he’s not able to accurately convey it. Some people with higher activity levels need carbohydrates in their diet, OR they can be substituted by as excessive protein intake.
How that’s relevant to us as diabetics (I’m only discussing T1 and T2 based on my knowledge level):
T2/Low Exercise- A LCHF diet often works great, but excessive protein consumption should probably be avoided as it eventually converts into glucose (which wouldn’t be used based on low activity levels)
T2/High Exercise- A LCHF diet often works great, but protein consumption may need to be increased to avoid muscle breakdown.
T1- An LCHF often diet works great, but for different reasons. High glycemic index carbohydrates can make it difficult to manage insulin doses. Substituting those High GI carbs for low GI carbs and/or excessive protein can have the same effect in replacing glycogen stores, but without the high blood sugar volatility.