Figure 2. Proportions of fatty acids in wild and commercial animal foods.
Examining these figures, two dominant trends emerge:
1. Wild meat is proportionally higher in protein and lower in fat compared to commercially raised meat.
2. The fat portion of wild meat is proportionally higher in PUFAs – both omega-6 and omega-3 – compared to commercial meat.
Additionally, we can say that grass-fed beef is closer to wild meat than grain-fed beef, but both grass-fed beef and grain-fed beef poorly approximate wild meat.
The above observations are based on data from the USDA Nutrient Database and are substantiated by numerous studies comparing wild and domesticated animals [3], [4], [5], [6], [7].
Additionally, scientists have recently extracted frozen, Paleolithic-era animal carcasses from the Siberian tundra. Tissue analyses of these carcasses further highlight the similarities between Paleolithic meat and modern wild meat, particularly with respect to n-6/n-3 ratios [8], [9].
The Ever-Important Omega Ratio
As we saw in part I, many RCTs, observational studies, and meta-analyses addressing omega-6 consumption fail to properly account for omega-3 consumption (and the n-6/n-3 ratio). For our Paleolithic ancestors, this ratio was approximately 1/1 (and probably no higher than 3/1) [10]. Today, however, the ratio approaches 20/1 for people consuming typical Western diets [11].
This disparity is critical to the entire debate about saturated fat and its replacement with omega-6. Recent studies show saturated fat isn’t a health menace, as previously believed [12][13][14][15]. On the other hand, our reliance on commercially raised meat has probably skewed our fat consumption by over-representing saturated fat and under-representing PUFAs. We’ve compensated by consuming large quantities of vegetable oils, which are rich in omega-6, but omega-3 consumption has fallen by the wayside.
The consequences of our dramatically elevated n-6/n-3 ratios include the following:[16]
- Increased inflammation
- Increased leptin and insulin resistance
- Increased risk for diabetes
- Increased weight gain and risk for obesity
Keeping it Real
Just as previous generations shunned saturated fat, we would be foolish to shun omega-6 completely. After all, omega-6 is an essential fatty acid (EFA), meaning our body requires it and can only obtain it from food. That being said, some sources of are better than others.
It’s easy to get good quality omega-6 from olive oil, avocados, nuts, and from certain animal foods. By following the Paleo Diet template, you’ll get a good balance of omega-6 and omega-3, plus a good distribution of SFAs, MUFAs, and PUFAs.
With respect to omega-6, our best advice would be to eliminate all vegetable and seed oils from your diet. These include, among others:
- Soybean oil
- Corn oil
- Safflower oil
- Sunflower oil
- Canola oil
- Grapeseed oil
The problem with these oils is they contain very high amounts of omega-6. Consuming them increases your n-6/n-3 ratio, while also introduces potentially dangerous free radicals.
Unstable Seed Oils
The industrial processing of vegetable seed oils involves high-heat and the use of various chemical solvents – a guaranteed recipe for free radical oxidation and lipid peroxidation [17].
Cooking with PUFA-rich oils creates lipid oxidation products known as alkenals, some of which are toxic [18].
Olive oil, which contains some PUFAs, but is mostly comprised of MUFAs, has been shown to be more heat-stable and better for cooking compared to vegetable oils [19],[20]. It’s best to avoid high-heat cooking with any oils, but those containing higher amounts of SFAs and MUFAs are more stable than those with higher amounts of PUFAs.
Conclusion
Saturated fat isn’t unhealthy, but it needn’t be over represented in our diets. Many health authorities recommend replacing saturated fat with omega-6, and although some studies support this recommendation, most fail to differentiate between omega-6 and omega-3. Replacing some saturated fat with PUFAs could be beneficial, particularly if doing so lowered the n-6/n-3 ratio. For most people, this would mean eliminating all vegetable seed oils, while increasing oily fish (omega-3) consumption.
It’s also important to recognize that meat from game animals is better than commercially raised meat, but since obtaining wild meat is impractical for most people, pasture-raised meat (grass-fed, etc.) should always be favored.
Don’t over complicate things too much. You don’t need to meticulously track your fat consumption. By following The Paleo Diet template and listening to your body, you’ll get a healthy mix.
References
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