In my nutrition class I took for nursing, my professor taught us what was essential...
LIPIDS (fats), because it's what literally keeps us from washing down the drain; CARBOHYDRATES, since our brains use this exclusively for fuel; PROTEINS, our bodies use this for growth and repair; VITAMINS + MINERALS assist in cell function; and finally WATER, because we're mostly water and thus need it to function.
What isn't essential are trans fats and saturated fats.
Try to avoid cholesterol in this question, since we do need a finite amount of it to function. If you have to, say it's ADDED CHOLESTEROL, we do not need to eat things like animal products for it, since our bodies make more once fiber pushes it out of our colon.