How can we prevent ourselves from being underweight, overweight, and obesity through diet?

Underweight is defined as having a  body mass index (bmi) under 18.5, or under healthy weight. Overweight is having a bmi of 25 to 29.9 bmi, or over healthy weight. Obesity is having a bmi of over 29.9, which is extremely over healthy weight. The first step in preventing all three of these situations is knowing your healthy weight range. For example, I am five foot, zero inches tall. My healthy weight range is 95 pounds to 128 pounds. As they say, knowing is half the battle. I can now set achievable goals based on knowing where I should be. I also just said a very important word in the that last sentence. This word is achievable. If you weight 200 pounds are your healthy weight range is 135 to 155 pounds, you are probably not going to reach a goal of 100 pounds and look like a supermodel, at least not naturally or healthily. Remember that we, as humans, as suppose to be at healthy weights. Also, keep a food journal. This will help you both stay accountable and remember what you have eating in a day. It is very easy to forget your morning snack of almonds or a donut by the time you sit down for dinner. And lastly, make sure that the foods you are choosing and fueling, not fighting your body. Eat plenty of nutrient-dense foods for optimal health (Sizer & Whitney, 2013).

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Reference:

Sizer, F. & Whitney, E. (2013).  Nutrition: Concepts and Controversies (13th ed.).  Mason, OH: Cengage Learning