An acid is a substance that gives up positively charged hydrogen ions (H⁺) when dissolved in water. A base (alkaline) gives up negatively charged hydroxide ions (OH^-) when dissolved in water. pH is a scale that measures of how basic or acidic a solution is. Numbered from 0 to 14, solutions with a pH of 7 are neutral, less than 7 are acidic, more than 7 are alkaline.

Anemia, which may cause weakness, dizziness, and headaches is caused by a lack of iron in the diet.

Minterals, vitamins, and fiber are micronutrients while proteins, carbohydrates, and fats are macronutrients.

Vitamin D helps calcium strengthen bones while also aiding muscle, nerve, and immune system function.

Radiation occurs when electromagnetic waves transmit heat. An example is the heat from the Sun as it travels to Earth.