Chronic dieter plunging into a new regimen yet again

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I'm a British Asian woman who has been trying to lose weight for the past decade. I started off as only slightly chubby, an insecure teenage girl who craved a pin-up body. But now it has reached the very serious point where my doctor has warned me that despite my young age, my South-Asian ethnicity and family history of diabetes means that I need to start making drastic lifestyle changes right now.

My current weight loss & fitness goals are:

August 15th, 2014 (my friend's wedding) : Lose 10 Kg at a rate of 1 KG / week and complete a 10 kilometre run

October 1, 2014 (the first day of my master's degree at a new university): Improve body tone and complete a half-marathon

1st January, 2015 (New Year's Family Reunion): Lose 5 further kg at the rate of 0.5 KG/ week

1st June, 2015 (End of master's degree): Lose a final 5 kg at a rate of 1 KG/ month and be in good enough shape to run a marathon


By this point, I should have lost 20 KG (44 Lb) and reduced my BMI from 28.1 (overweight by normal standards but alarmingly high for a South Asian woman with family history of diabetes) to 20.5 (on the lower side of healthy by normal standards, but ideal for my situation). Please wish me luck, and more importantly, perseverance and will-power, because I am going to need it!