walnuts in shells in an old wooden bowl. snack. a source of omega-3 for the brain. healthy food concept. close-up.

agriculture antioxidant autumn background bowl brain brown christmas close closeup concept copy copyspace cracked decoration diet elements food group health healthy heap horizontal husk ingredient kernel kitchen macro natural nut nuts nutshell nutty old omega3 ripe season seed shell shells single snack source space tasty top trace vegetarian view walnuts wooden