Could one sex be more efficient at weight loss than the other sex?
My wife and I started PB at the same time. (Albeit, just one month ago) We've been following the “program” identically and together; eating the same foods & portions at the same time, exercise the same, sleep at the same times...yet I have lost substantially more weight in the same time period than she has. 16 pounds to her 5 pounds.
(Some possibly helpful stats: Both age 56. I started at 203 lbs, with 24% BF and a BMI of 26.5. She started at 185 lbs, with 38% BF and a BMI of 34.2)
So...given identical controls, is it at all possible simply because of our inherent male or female body chemistry, fat distribution, hormones, etc, that one sex COULD loose more weight over the same time period given the same circumstances? If not, what else could come into play?
Heaviest: 1-22-2012 = 203 lbs, of being skinny fat, beginning PB
Current: = 182 lbs. 14% body fat.
Goal: 175 lbs. was made in April 2013.
F 5 ft 3. HW: 196 lbs. Primal SW (May 2011): 182 lbs (42% BF)... W June '12: 160 lbs (29% BF) (UK size 12, US size 8). GW: ~24% BF - have ditched the scales til I fit into a pair of UK size 10 bootcut jeans. Currently aligning towards 'The Perfect Health Diet' having swapped some fat for potatoes.
Okay, first, let's look at the percentage of body weight lost since you're not the same size.
For her, 5 pounds lost at 185 pounds is 2.7%.
For you, 16 pounds at 203 is 7.8%.
So yes, there's a difference, but it's not the 3x difference it initially appears to be.
Secondly, women do tend to have a harder time losing fat than men. It sucks, but on average our bodies hang on to more fat. There are hormonal causes for this (androgen levels and so on), and if you consider the evolutionary reasons that are likely at play, it makes sense that women hold onto more fat than men. Our levels of essential body fat are different too--a woman at 12-15% fat is pretty lean, while a man at those levels is healthy but not ultra lean.
Thirdly, if you're eating identical portions, compared to each of your (probable) daily needs she's actually restricting less than you are since you are a larger person with a higher percentage of lean body mass. I have come to realize that I can't eat as much as my partner does and assume that's a reasonable portion for me, since he is about 230 pounds and I'm about 160. I simply do not need as much food as he does (especially considering his work and his low body fat levels).
“If I didn't define myself for myself, I would be crunched into other people's fantasies for me and eaten alive.” --Audre Lorde