PUFAs, whether Omega 6 or Omega 3 have a high tendency to carry free radicals to the lining of blood vessels and other sensitive tissues. This is because they have multiple double bonds which can open up and add oxygen containing groups. These free radical groups cause scars in blood vessels that begin the process of atherosclerosis. Saturated and monounsaturated fatty acids have very little capacity to carry reactive oxygen groups because they have zero (saturated) and one (MU) double bond, and in the case of MUFAs the one bond is generally resistant to reactivity. Saturated fats have no locations to add reactive oxygen groups.
PUFAs (omega 3 and 6) very easily add reactive oxygen groups. Cholesterol levels probably rise when arterial scarring has occurred because the cholesterol is a healing agent that reinforces the damaged blood vessel lining-so high cholesterol is most likely a symptom, not an instigating cause in atherosclerosis. Reducing cholesterol for someone who does not already have advanced atherosclerosis likely prevents healing of the scarring. Only after severe scarring has occurred, coupled with calcium buildup, does cholesterol possibly start to backfire by building up around the sclerotic sites. (Again, blood cholesterol CAN be a sign of blood vessel scarring because the body produces it to heal the scarring).
Anyway, the balance of omega 6 to omega 3 has to do with inflammatory balance in the body. High levels of omega 6 cause chronic inflammation, and if you eat them when gaining fat, they will build up in adipose. This is one possible reason why some people have heart attacks when they start to lose weight, because they have high levels of omega-6 in their adipose which gets released when they start to mobilize the fat for fuel. The body even has a tendancy to store excess omega 6 as adipose to keep it out of circulation. Omega 3 during this fat loss period period can help to reduce the inflammatory effects. Omega 6s eaten during a fat loss period are not a big issue because in a period of calorie reduction, they are largely burned for fuel. Being in a hypocaloric state reduces a lot of the harms of certain energy substrates like omega 6 and fructose because they get burned rather than built up.
There is no evidence of any increased health hazzards from up to about 10 grams of total PUFAs per day. There is SOME evidence of increased health hazzards when PUFAs exceed 10 grams a day, but again, it may depend on whether one is in a hyper or hypocaloric state. There is no evidence of benefits from long term intake of more than about 3 grams of omega 3 fatty acids per day if omega 6 is kept optimal. So that would mean that in a perfect situation, you might consume about 3 grams of Omega 3 and 3-7 grams of omega 6. Most people get way too much omega 6 though, and adding omega 3 can balance the inflammatory effects, but remember that they both carry free radicals around the bloodstream.
Taking more than 3 grams of omega 3 per day for periods of time MIGHT be beneficial during fat loss IF the individual has build up their adipose on a diet high in Omega 6 and therefore is releasing lots of Omega 6 during the fat loss period. Poliquin believes that mega dosing of fish oil can help with rapid fat loss, and if so, it is probably because it helps counter-balance the body’s tendancy to not release omega-6 into circulation because of the inflammatory effects. (The body might be resistant to mobilizing fat that is high in omega 6 but less resistant when omega 3 is there to negate the inflammation). He recommends up to 20-40 grams of fish oil a day for rapid weight loss, but the typical fish oil tablets when he made that recommendation were only about 30% omega 3, so that would be 7-14 grams of actual omega 3 fatty acids per day. He does not recommend this in the long term and I don’t know if there is science to support his belief. I think it might depend on whether the overfat person built up their fat reserves on a high omega 6 diet.
New omega 3 supps like Flameout are close to 60% omega 6. Flameout also have a benefit of having a ratio of DHA to EPA that is supposed to be optimal for men. Tip: Stop Using Fish Oil Made For Women
As omega 6 rises above about 6-7 grams a day, there is some benefit in adding some omega 3, but there are also some potential harms (arterial scarring). This is probably why omega 6 supplementation data has shown conflicting results for cardiovascular health. Again, it also depends on caloric state, and whether there as already atherosclerosis in blood vessels. Increasing omega 6 from 3-7 grams up to 10-15 grams on maintenance calories would still have your omega-6 in the low end of health hazzards. I can’t tell you if adding a little omega 3 would be better or worse as it would likely depend on the other factors.