Here’s why nutrient deficiencies should concern you: You may be wondering if this risk is really that bad. I mean, what really happens if you’re low in one or two vitamins or minerals? The answer is that there is a lot to be concerned about. Vitamins and minerals are called “essential” for a reason: they truly are essential for optimal health. Your body needs important nutrients to function correctly. If you are low in those nutrients, you could experience issues with your physical and mental health.