Natural Grass-fed beef is the best core immunity builder. Especially if you are over 60 years, you need all the immunity you can get! Natural grass-fed beef is best, and wagyu fats are even richer in omega's than normal beef!
Get the core immunity builders from beef: Zinc, Iron, Omega A and Vitamin B. It is the single most potent immunity building food. Natur Beef - natural and wild grass-fed wagyu/angus cross beef.