Dieters need at least 1,000 to 1,200 calories per day for normal body function. Drinking meals instead of eating meals may lead the dieter to a feeling of deprivation. Deprivation is one of the most common reasons why dieters stop dieting. This allows the dieter to lose an average of one to two pounds a week, more if they exercise regularly. Secure does not mention exercise as part of the weight loss program. The shakes are packed with vitamins and nutrients, so dieters could consume more than 15 per day to meet calorie goals, but that would be an expensive trade-off for real food. Secure is a weight loss shake that claims to be a meal replacement though it contains only 70 calories per serving. Consuming only 70 calories per meal is not enough to keep the body in good working order.