It’s estimated that the Old Stone Age diet provided much more omega-3 fatty acids and much less omega-6s, compared to modern Western diets. This may have important implications for development of certain chronic diseases like cancer and heart disease.
Fatty acids, by the way, refer to the long chains of molecules that comprise the majority of fats and oils.
Some folks speculate that the Stone Age (Paloelithic) diet may be the healthiest way to eat because our genes are adapted to it. In other words, we evolved in a certain food environment over hundreds of thousands of years, so we should have optimal health if we follow our ancestral diet (whatever that is).
A major change in human eating habits over the last century has been the dramatic increase in consumption of industrial seed oils like corn and soybean oil. These have dramatically increased the omega-6 fatty acids in our diets. i.e., they’v3e increased the omega-6/omega-3 ratio. Another major change starting about 10,000 years ago is the increase in consumption of grains.
I haven’t studied omega-6/omega-3 ratio issue in great detail but hope to do so at some point. Evelyn Tribole has strong opinions on it; I may get one of her books.
I saw an online video of William E.M.Lands, Ph.D., discussing the omega-6/omega-3 ratio. He mentioned free software available from the National Insitutes of Health that would help you monitor and adjust your ratio.
You can see the video here. Dr. Lands’ talk starts around minute 12 and lasts about 45 minutes. He says it’s just as important (if not more so) to reduce your omega-6 consumption as to increase your omega-3. And don’t overeat.