The nutrients in foods can vary depending on growing conditions, and other factors. For example, fruits grown in magnesium rich soil will likely have more magnesium that those not.
How much do nutrients vary in general? According to data from the U.S. Agricultural Research Service there is not a lot of deviation in nutrient content, with most nutrients not fluctuating more than 5%. Nutrients which do fluctuate the most include Omega 3 fatty acids (EPA, DHA), Vitamin D2, fluoride, Vitamin K1, and K2, and copper. All other nutrients only fluctuate by 5% or less. Below is a ranking of 82 nutrients, how much is in each food on average, what the average standard deviation is, and what the percent of fluctuation or standard deviation is. Subscribe to MyFoodData.com for more articles on what causes nutrients to fluctuate in foods.