Liquid Vitamins

• Liquid vitamins are fresher and more potent than pill form, so they require refrigeration to maintain this freshness and potency. Vitamin pills contain preservatives that increase their shelf life. Since liquid vitamins do not contain these additives they require refrigeration.
  
  

Fish Oils

• Fish oils contain essential fatty acids and can help reduce cholesterol.Ryan McVay/Stockbyte/Getty Images
  
  Fish oils are an essential fatty acid. Because of the high levels of omega-3, fish oil supplements can reduce cholesterol and possibly reduce inflammation. Liquid formulas are light-sensitive, which is why they are usually packaged in opaque bottles. Once you have opened them, they are also exposed to oxygen and can spoil if left out of the refrigerator.
  
  

Flaxseed Oil

• Flaxseed oils contain a high concentration of plant lignans.Hemera Technologies/Photos.com/Getty Images
  
  Like fish oil, flaxseed oil is a good source of omega-3 essential fatty acid. It is also a great source of fiber and protein. Flaxseed oil contains a high concentration of plant lignans, phyto-nutrients that are beneficial to human health. Also, like fish oil, flaxseed oil can help reduce inflammation and cholesterol. If flaxseed oil is in liquid form, seal tightly and refrigerate after opening.
  
  

Probiotics

• Probiotics are a health-promoting bacteria used for digestive health. Forms of probiotics include acidophilus and other live bacteria supplements. Since they contain active cultures that can die if exposed to heat, light and air, it is essential that you refrigerate them.