Interesting how his example is a guy who ate 2 McD's double cheeseburgers a day with no bun and diet soda.
That's it.
Not sure how that's sustainable for an average person.
That would keep me full for about 45 minutes. 
I ate 2 pounds of 80/20 ground beef yesterday and 2 pounds of ribeye steaks.
My food bill has more than doubled since i started carnivore.
A few weeks ago i ordered 6 - 1/4 pounder beef patties from McD's by itself.
I was starving 4 hours later.
Some of these stories make me question many things. The guy he used as an example was eating like 500 calories a day.
The patient claimed he ate 2 double cheeseburgers per day with no bun and diet soda on days he wasn't hungry, and 3 on a typical day. That's around 850 calories, if you believe nutritional sites on the interwebs. I'm sure there were days when he ate more, or added eggs and bacon for breakfast, but didn't report it. That's the problem with self reported data.
Eating so few calories was probably temporary, until he lost the weight he needed to lose.
Undereating is not rare in people who adopt a meat only diet, because hunger and cravings go away. Those people have to intentionally eat more depending on their goals at the time.
The guy likely didn't exercise at all. Many of Dr. Westman's patients can't exercise or just don't. He doesn't discourage exercise, but doesn't push it either especially in the beginning.
In his experience in clinical practice and in his published research, the most important and effective factor for his patients has been to keep the carbs very low long term, while eating lots of satiating nutrient dense foods such as fatty meat and whole eggs.
I personally prefer Whopper patties myself if I'm out running errands, get hungry on my way home, and don't feel like cooking. I take them home and then add my own smoked cheddar cheese and my own Kirkland pre-cooked bacon.
I used to eat 8 Whopper patties in one sitting, with or without cheese and bacon, and that's all I'd eat all day. Eventually it got to the point I could only eat 4 or 6.
These days I rarely do that anymore. I've been eating 8 egg yolk and bacon omelets for breakfast, sometimes I add butter and/or cheese. For my second and final meal of the day, I'll eat a small ribeye steak with plain salt or 1 lbs fatty ground beef with my own homemade taco seasoning. If I get the munchies later, I'll eat pork rings, or more bacon, or a 1/2 cup of heavy whipping cream with a drop of vanilla extract and a drop of liquid Sucralose.
My food bill is the same at worst, much lower at best. Before keto/carnivore I used to eat meat and eggs, but also organic fresh produce, nuts and seeds, and a long list of other plant based foods (oats, rice, bread, pasta, tortillas, peanut butter, etc.). A lot of that stuff would often go to waste because it would go bad before I could eat it. I ate 3 meals a day plus healthy snacks in between because I was hungry all the time. I also took a lot of supplements, and was on some medications too.
Now I just buy the meat and eggs, a little cheese and heavy cream occasionally, I eat only 1 or 2 meals a day, I rarely waste food if ever, I no longer take any supplements other than magnesium, and after doing this diet long term I am off my medications. I'm no longer shackled to the food, pharma, and supplement industries. One of the best decisions I've ever made, for my health, for my sanity, and for my wallet.
