I am always cold and tired. i just got a blood test and all of my levels are normal, and my diet is stellar, so what could be causing my fatigue?

Many things!: There are many possible causes: infections (bacterial, viral, fungal, parasitic), nutrient deficiencies (like low vit d), toxic exposures, thyroid ; adrenal problems, sleep disorders, heart disease, stress, depression etc. Most of these don't show up on standard tests. Cold ; tired is classic for thyroid but you need thorough tests: http://bit.Ly/1cjnybx see a holistic doc: http://bit.Ly/19pettq.