It should be called "yo-yo dieting" if im not mistaken.
Answer:
Examples of paradigm shifts are the movement of scientific theory from the Ptolemaic system (the earth at the centre of the universe) to the Copernican system (the sun at the centre of the universe), and the movement from Newtonian physics to the theory of relativity and to quantum physics.
Explanation:
At the least, once a year.
This can vary between people with certain partners and such. You should test before symptoms appear because usually, once symptoms appear, it is too late to be cured or treated.
Every six months can be frequented and sometimes preferred but is not required. Once a year is the least a person could do to test for STD's.
Hope this helps!
