I had hoped to have time to write a great posting and all of the information I found out this weekend concerning Leptin. But, I am short on time this week. So, let me just briefly spell it out for you and hopefully later I can list some supporting evidence.
Leptin is a chemical that your fat cells release to tell your brain not to eat. Just about all people who are over weight are "leptin resistant". Similiar to insulin resistence, leptin resistince is when the brain is no longer able to pick up the leptin to recieve the message to stop eating. They have found that this is the case in almost all over weight/obese people because of triglycerides in the blood stream (in fact one article stated you would have to be a very special case to be over weight and not have this issue). Triglycerides apparently stop leptin from crossing the brain blood barrier and therefore leptin can't communicate with the brain. So, if you are like me and always feel hungry and never feel satisfied from your food this is probably a major reason (although don't under estimate the power of emotional eating which has the same symptoms).
Now, triglycerides are part of the lipid (fat) panel your doctor should be testing every year along with things like good and bad cholesterol. But, triglycerides don't come from eating too much fat instead they come from eating too many simple carbs and sugar. Traditionally scientists thought that leptin resistance was caused by eating fatty foods but now that is starting to be disproved. Now science seems to be realizing that a low carb diet works better on correcting the leptin/triglyceride issue. This is why so many people who have used a low carb/paleo diet may have been able to stick with those diets because for the first time in a while the person wasn't raveneously hungry and was able to lower their calorie in take.
But, new information is starting to come out about how to deal with resetting your body to better deal with leptin. This information suggests that moderately brisk exercise does a better job at healing leptin resistance than modifying food choices. In an article I read over the weekend (I believe it was in "First for woman") it quoted some studies that found moderately brisk walks of 30 minutes or more, done five days a week, will correct this situation as well.
Why is this so important to me?
1) I am always hungry which is really annoying.
2) Low fat diets only leave me starving and in a bad mood.
3) About a year ago I did kettlebell training which was amazing but it is a very high intensity workout that left me ravenious afterwards. I believe it was just too tough of a training workout and instead of helping me lose weight I gained weight on it. But, I still believed if you didn't kill yourself working out you were not doing enough.
4) this study gives me permission to just do walking or kata as my workout because I can still lose weight while not killing myself or increasing my apetite.
(I wrote this quickly and don't have time to really proof read it so hopefully it makes sense)