Weighing In: Can A Diet Increase Metabolism?

It is absolutely possible to get all vitamins and minerals, as well as a full range of phytonutrients, on a low carb diet - in fact, it is not hard at all.  The trick is to eat a lot of non-starchy vegetables, a little low-sugar fruit, and and some nuts and seeds.  You don't need to eat foods with lots of sugar and starch to eat a balanced diet.

No matter how you lose weight, if you go back to eating the old way you will regain, and for some of us unfortunates, it means weighing more than we used to.  I have kept a moderate amount of weight off for over 5 years, and have other health improvements which are even more important, but I'm dedicated to staying away from sugar and starch for life AND eating lots of veggies, etc. 

I also think treating yourself once per week keeps your body from adapting to your diet. If you eat the same number of calories every day, week in and week out, eventually your body is going to adapt to that. After a while, the results of eating a restricted diet won't be as significant. To vary my caloric intake, I treat myself to an ice-cream bar or something similar once per week. The body is so predictable in its ability to adapt. For this same reason, it's important to change up your exercise routine every 3 weeks or so.

I've seen conflicting opinions on whether "starvation mode" exists, and could use references to studies on this.

For one, there are an increasing number of studies showing the dramatic health benefits of calorie-restricted diets, including those calling for intermittent fasting--and with no "starvation mode" effect.

Second, there seems to be a difference between whether "starvation mode" is a result of skipping meals, or of attaining extremely low body-fat composition.  The latter seems to make more intuitive sense than the former--are there specific studies that support or contradict either/both?