vannakam! you can start by switiching to brown rice! cut out the appalamas and upma. have a lot of kuttu and sambhar.
here is what my dietician suggests - follow a practical diet. have a snack every three hours. fruit or soy nuts. Make sure your plate has this ratio - 50% veg, 25% carb, 25% protein.this will prevent cravings too. pick a exercise regime you like. but lose only 1 kilo(2.205 pounds) a week. that is the permanent way of losing.

1. Chew your food to a pulp or milky liquid until it practically swallows itself.
2. Never eat until hungry.
3. Enjoy every bite or morsel, savouring the flavour until it is swallowed.
4. Do not eat when tired, angry, worried, and at mealtime refuse to think or talk about unpleasant subjects.
Horace Fletcher followed these rules for five months. As a result he lost more than 60 pounds and felt better than he had for 20 years. A weight-reducing programme built on Fletcherism works wonders and is worth a trial.
Ingestion of honey is an excellent home remedy for obesity. It mobilises the extra deposited fat in the body and puts it into circulation which is utilised as energy for normal functions. One should start with small quantity of about 10 g to be taken with hot water. The dose can be gradually increased.
Fasting on honey-lime juice water is highly beneficial in the treatment of obesity without the loss of energy and appetite. In this mode of treatment, one spoon of fresh honey should be mixed with a juice of half a lime in a glass of lukewarm water and taken at regularly intervals. Another effective remedy for obesity is an exclusive lemon juice diet. On the first day the patient should be given nothing but plenty of water. On the second day juice of three lemons mixed with equal amount of water should be given. One lemon should be subsequently increased each day until the juice of 12 lemons is consumed per day. Then the number of lemons should be decreased in the same order until three lemons are taken in a day. The patient may feel weak and hungry on the first two days, but afterwards the condition will be stabilised by itself. Cabbage is considered to be an effective home remedy for obesity. Recent research has discovered in this vegetable a valuable content called tartroric acid which inhibits the conversion of sugar and other carbohydrates into fat. Hence, it is of great value in weight reduction. A helping of cabbage salad would be the simplest way to stay slim, a painless way of dieting. A 100 g of cabbage yields only 27 kg of calories of energy while the same quantity of wheat bread will yield about 240 calories. Cabbage is found to possess the maximum biological value with minimum calorific value. Moreover, it gives a lasting feeling of fullness in the stomach and is easily digestible.
Along with dietetic treatment, the patient should adopt all other natural methods of reducing weight. Exercise is an important part of weight reduction plan. It helps to use up calories stored in body fat and relieves tension, besides toning up the muscles of the body. Walking is the best exercise to begin with and may be followed by running, swimming, rowing, and other outdoor sports.
Certain yogi asanas are highly beneficial. Not only do they break up or redistribute fatty deposits and help slimming, but they also strengthen the flabby areas.
Sarvangasana, halasana, bhujangasana, shalabhasana, dhanurasana, chakrasana, naukasana, ardh-matsyendrasana, paschimottanasana, vajrasana, yogamudra, and trikonasana are recommended. These asanas work on the glands, improve circulation, strengthen many weak areas and induce deep breathing which helps to melt off excess fat gradually. Yogic kriyas like kunjal and jalneti and pranayamas such as kapalbhati and bhastrika are also helpful in normalising body weight.
The patient should also adopt measures which bring on excessive perspiration such as sauna baths, steam bath, and heavy massage. They help to reduce weight. Above all, obese persons should make every effort to avoid negative motions such as anxiety, fear, hostility and insecurity and develop a positive outlook on life.
Hope this helps, Good Luck.

u r in luck...b'coz i'm a south indian girl and i used to be very fat...but i reduce 13 kgs just by following my own regime..but plz be very dedicated...i planned to lose 1kg per 1 week...morning--half an hour exercise,like yoga or aerobics..
drink 1 glass of milk(with very little sugar)...slim milk is preferable...eat idli or dosas or anything w/o oil....that too only two idlis or 1 dosa....for lunch strictly 1 cup of rice and any curry....less oil...no non-veg....evening--1 hour of very rigourous exercise(compulsory) like brisk walking or fast dancing or aerobics...remember for 1 hour....dinner--1 bowl of thin soup(u can opt for maggi soups which r easy to prepare) and 1 fruit(but not banana)....that's it this regime will surely make u lose weight...1 kg...1 week...

a regime was the Nazi's....learn English
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