I think that if the diabetes is diagnosed early enough in the process...and it is a linear process, then some people may be able to stop the process in it's tracks. However, they would still have a tendency to become glucose intolerant and stopping the healthy eating regime, or being unable to continue the same amount of activity might cause more insulin resistance again.
Unfortunately by the time some people are diagnosed the process has been going on for some time with some loss of beta cell function so they may not be able to 'reverse' their condition. Also, not all people labelled as T2 are overweight, and perhaps there are several variants of T2, some more likely to respond well to diet and exercise than others
Here's a simple report in a Diabetes Journal, they use the word reversal here:
Reversal of Type 2 diabetes in the context of bariatric surgery is currently of great interest. Discussion of the rapid and dramatic effects of bariatric surgery upon the pathophysiology of Type 2 diabetes has concentrated almost exclusively on surgically induced change in the incretin hormones [1,2]. Little consideration has been given to reversal of Type 2 diabetes by the effects of caloric restriction alone. We report a person with Type 2 diabetes who returned to normal fasting blood glucose and glycated haemoglobin (HbA1c) after reading a notice about a grant award in Balance concerning the effects of a hypocaloric diet on glucose control
Dietary reversal of Type 2 diabetes motivated by research knowledge
http://onlinelibrary.wiley.com/doi/10.1111/j.1464-5491.2010.02992.x/full
Actually the full story isn't so different to some we read on diabetes forums.The lady lost weight, fasting glucose and HbA1c came down. We don't know about an OGTT
One study back in in 1982 looked at the treatment of T2 on diagnosis by diet alone and did do another OGTT.The subjects were put onto a diet varying between 1000 and 1800 calories a day (individualised according to weight, gender actiivity levels etc) 40% of the diet was carbs.
After 3 months they had another OGTT. Of the 182 patients studied,
25.4% average improvement in glucose tolerance,
37 subjects "became well-controlled in that the area under the glucose response curve after treatment became normal
"29 subjects " were poorly-controlled as the area under their glucose response curves remained at least twice the upper limit of normal.'.
."Those patients whose glucose tolerance became normal were mainly men, and were significantly heavier and had significantly less glucose intolerance before treatment than those patients who remained poorly controlled. On diet therapy the well-controlled patients lost more weight and showed a significantly greater fall in plasma triglyceride levels."
Did those people sustain their 'normal' glucose tolerance status? We don't know. One thing is clear is that the researchers' invested a lot of time and effort in teaching and supporting people in their diets, they weren't just given an instruction sheet to take away with them.
Treatment of Type 2 (Non-Insulin-Dependent) Diabetic Patients with Diet Alone
http://www.springerlink.com/content/l64x431508p21739/fulltext.pdf
Another paper here is far too detailed to summarise. It also suggests that reversal is possible by diet in early diagnosed cases of T2.
Pathogenesis of type 2 diabetes: tracing the reverse route from cure to cause
http://www.springerlink.com/content/j088876181l3qu55/fulltext.pdf
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