Walnut is a Green-Green food. Green-Green foods are very safe to eat as a regular part of a diet.
Guideline related quotes related to Nuts and Green-Green throughout Geoff Bond's publications.
All tree nuts are acceptable sources of good protein, as well as products made from them ~Paleo in a Nutshell p.48
Nuts are a natural food for humans to be consuming. All tree nuts are generally fine. ~Paleo in a Nutshell p.72
Nuts should be raw and fresh. ~Paleo in a Nutshell p.72
Nuts classified "Green-Green" have a high omega-3 content. ~Paleo in a Nutshell p.73
For Green and Green-Green categories, All nuts must be fresh, raw, and unsalted. ~Paleo in a Nutshell p.73
Examples of one serving include 1/3 cup nuts; 2 tablespoons almond, cashew, etc. butter (not peanut butter). ~Paleo in a Nutshell p.95
For nuts group, Consume at least seven servings of “Green-Green” foods per week. ~Paleo in a Nutshell p.103
For nuts group, Restrict total nuts servings per session to one. ~Paleo in a Nutshell p.103
For nuts group, Restrict total nuts servings per day to two. ~Paleo in a Nutshell p.103
Nuts are often called "tree-nuts" to distinguish them from the peanut, which grows underground and is a legume. ~Deadly Harvest p.64
Specific references to Walnut throughout Geoff Bond's publications.
All tree nuts are generally fine. Examples are walnuts, almonds, Brazil nuts, and filberts. However, chestnuts, coconut, and peanuts do not fit into this tree nut category. Chestnuts are mainly starch and so are included in the starchy vegetable group; coconuts are mainly oil and are included in the fats and oils group. Peanuts are not nuts; they are a legume and are included in the previous legume group. ~Paleo in a Nutshell p.72
Almonds, walnuts, pistachios, and chestnuts are all native to the Fertile Crescent and were domesticated early during the farming revolution. The Brazil nut and the cashew nut are native to South America, the pecan to North America, and the macadamia to Queensland in Australia, and all of these nuts have become familiar to us in the West. They are often processed in various ways, notably by roasting and salting, which improves shelf life and taste, but it is not a nutritional improvement. ~Deadly Harvest p.65
Omega-3 EFAs are found in plants and animal matter. In plants, the most common form is alpha-linolenic acid (ALA), found particularly in walnuts, flaxseed, hempseed, and rapeseed (canola oil). In animals, omega-3 oils are particularly found in "oily" fish, such as sardines, salmon, trout, and tuna. ~Deadly Harvest p.104
Walnuts have the exceptional property of being rich in omega-3 oil. However, it is essential that the walnuts be fresh, because their omega-3 oil turns rancid very easily and becomes an oxidized fat particularly harmful to cardiovascular health. ~Deadly Harvest p.151