Tea contains antioxidants called flavonoids, which provide many of the health rewards. Flavonoids, however, bind to the nonheme iron found in plant foods such as beans and vegetables as well as dairy products. If you drink your tea with these foods, therefore, your body may not be able to access some of the iron. To maximize absorption of this important nutrient, limit tea drinking to between meals only, or add a spritz of lemon to help counter the iron-binding effect.
it can have a lot of impurities in it, which can cause sickness, headache or a general bad feeling. This can happen if your coffee is made from beans that have been over ripped or otherwise ruined. Even one ruined bean can make your cup toxic. If you invest and buy high quality, speciality coffee you don’t have to worry about this.
Again, it's the caffeine working here. Your recommended maximum amount of caffeine is 400 milligrams, roughly the amount that you’ll get from 4 cups of coffee. If you’re caffeine-sensitive, be careful with coffee. You are probably already aware what amount and what kind of coffee suits, or doesn't suit you
So if I had to choose, it would be tea.