Anorexic women also suffer great imbalances in the sex hormones, which opens a whole other can of worms. In more severe cases, even neurological and bone marrow damage can occur. 100 calories a day is much less than what people ate in concentration camps. Your gf has SEVERE problems. According to the Mayo Clinic, you need to burn about 3,500 calories to lose 1 pound of weight. That means if you decrease your daily calorie intake by 500 to 1,000 calories, you can expect to lose 1 to 2 pounds per week. If it's the right amount for you, use an online weight-loss calculator for a 1,300-calorie diet to see what kind of progress Most female adults need 1,600–2,200 calories per day, while adult males need 2,200–3,000 calories per day. However, the amount of calories you need each day is unique to your body and activity There's a chance that having too much protein in your diet could lead to brittle bones. According to a 2013 review of studies, high levels of protein consumption may be associated with poor bone health due to calcium loss. However, another 2013 review found that the effect of protein consumption on bone health cannot be determined. An extra 300 calories a day — half a sandwich and a glass of skim milk — might be enough to help you meet this goal. For people who are overweight or obese, the guidelines translate to a weight gain of about 1/2 pound (0.2 kilogram) a week in the second and third trimesters. Now, eating small meals more frequently doesn’t mean you are automatically going to lose weight. You still need to be within a calorie deficit: to lose weight, you need to eat less calories than you burn in a day. So, let’s say you eat 1500 calories and you burn 2000 calories in a day. That creates a reasonable calorie deficit of 500 calories. Dont be too hard on me! TL;DR: I'm starting to incorporate calorie deficit to lose more weight but online calculators vary and one suggested as low as 900cal per day (which is a 500 deficit). Need advise if it's okay to just go for 200 deficit. Really. Mostly it causes electrolyte and vitamin deficiencies. Potassium is a big one bc it impacts your heart. Lethargy is also linked to Vitamin deficiencies, 300 a day is seriously dangerous. The energy thing (calories) will still be ass. You'll swap over into ketosis (burns fat for fuel rather than sugar). Cycling. There’s nothing like a nice evening bike ride when the weather’s nice, and it’s actually a great workout too. A long, steady bike ride can burn up to 500 to 700 calories in an hour My entire set of problems was funneled into a single uber-problem: getting through the day on 600 calories. After a while, I ditched Dr. Stillman's low-carb plan in favor of a low-fat, low-calorie dqfOs48.