A recent study has suggested that almonds, specifically the skin of almonds, may support immune system function. The role of foods in immune management is increasingly of interest to practitioners as well as patients. The change in our dietary intake of basic food stuffs has changed dramatically over the last 100 or so years and the impact of this on health and disease remains an area of considerable exploration.
In this study, the scientists subjected 1.5 grams of blanched or natural almond skins to simulated stomach and intestinal digestion, intestinal digestion, or both using a previously explained method which incorporates sodium hydroxide, enzymes, bile salts, and calcium chloride. The control group of blanched and natural almond skins were exposed to salt water solutions with no enzymes.
Response to Viral Challenge
The researchers then exposed the different groups of almond skins (60 micrograms/milliliter in each group) to human white blood cells for 24 hours. The researchers exposed a segment of each group to a virus (herpes simplex virus, [HSV-2]) for another 24 hours to measure cell protection against viral infection.
How much do we need to eat?
Almond skins are the dark outer covering of almonds that is removed in blanching. The percent skin in almonds varies with the variety, but constitutes in the range of 10% of the almond. To Achieve the same levels in consumption as used in the study you need to eat 3 ounces/85 grams of almonds daily.
What did the almond skins do?
Only the natural almond skins exhibited anti-viral protection. Specifically, levels of immune markers, such as Interferon –alpha (IFN-α), Interleukin -12 (IL-12), IFN-gamma, and Tissue Necrosis Factor-alpha (TNF-α) all significantly increased when exposed to digested natural almond skins. In addition, markers of an antibody response (T-Helper-2 [TH-2] cytokines), i.e., IL-10, and IL-4 also were also found. These markers are all representative of the body’s healthy response to viral exposure.
“this suggests that (natural) almond skins (may) stimulate the immune response and thus contribute to an antiviral immune defense.”
The ingestion of natural almonds inclusive of their shells during periods of viral exposure risk as well as when under viral burden may offer an additional strategy to aid in the recovery of the infected or exposed individual. Almonds are a source of calcium, iron, magnesium, manganese, copper, zinc, phosphorus, B6, vitamin E and potassium.
 Arena A, Bisignano C, Stassi G, Mandalari G, Wickham MS, Bisignano G. Immunomodulatory and antiviral activity of almond skins. Immunol Lett. 2010 Aug 16;132(1-2):18-23. Epub 2010 May 11. View Abstract
 Mandalari G, Tomaino A, Rich GT, Lo Curto RB, Bisignano C, Saija A, et al. Polyphenol and nutrient release from skin of almonds during simulated human digestion. Food Chem 2010; 122:1083–8. View Abstract