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Scientifically Proven Health Benefits of
Oil No. 62
1. Introduction
The uses and properties of almond oil
Almond oil [Oleum amygdalae] has long been used in complementary medicine circles
for its numerous health benefits. Although no conclusive scientific data exists currently,
almonds and almond oil have many properties including anti-inflammatory, immunityboosting and anti-hepatotoxicity effects. Further, associations between almond oil and
improved bowel transit have been made, which consequently reduces irritable bowel
syndrome symptoms. Further, some studies show a reduced incidence of colonic cancer.
Moreover, cardiovascular benefits have also been identified with almond oil elevating the
levels of so-called 'good cholesterol', high-density lipoproteins (HDL), whilst it reduces lowdensity lipoproteins (LDL). Historically, almond oil had been used in Ancient Chinese,
Ayurvedic and Greco-Persian schools of Medicine to treat dry skin conditions such as
psoriasis and eczema. Further, it is through anecdotal evidence and clinical experiences that
almond oil seemingly reduces hypertrophic scarring post-operatively, smoothes and
rejuvenates skin. Almond oil has emollient and sclerosant properties and, therefore, has
been used to improve complexion and skin tone. Further studies looking into the use of
almond oil post-operatively for the reduction of scarring are suggested.
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2. Chemical components of Almond Oil
3. Clinical studies
Antioxidant activity
Antioxidant polyphenols in almond and its coproducts
Antioxidant efficacy of defatted almond whole seed, brown skin, and green shell cover
extracts was evaluated by monitoring inhibition of human low-density lipoprotein (LDL)
oxidation, inhibition of DNA scission, and metal ion chelation activities. The total phenolic
contents of ethanolic extracts of brown skin and green shell cover of almond were 10 and 9
times higher than that of the whole seed, respectively. Brown skin extract at 50 ppm
effectively inhibited copper-induced oxidation of human LDL cholesterol compared to whole
seed and green shell cover extracts, which reached the same level of efficacy at 200 ppm.
Green shell cover extract at 50 ppm level completely arrested peroxyl radical-induced DNA
scission, whereas 100 ppm of brown skin and whole seed extracts was required for similar
efficiencies. All three almond extracts exhibited excellent metal ion chelation efficacies.
High-performance liquid chromatographic (HPLC) analysis revealed the presence of
quercetin, isorhamnetin, quercitrin, kaempferol 3-O-rutinoside, isorhamnetin 3-O-glucoside,
and morin as the major flavonoids in all extracts.
In vitro activity of almond skin polyphenols for scavenging free radicals and
inducing quinone reductase
Observational studies and clinical trials suggest nut intake, including almonds, is associated
with an enhancement in antioxidant defense and a reduction in the risk of cancer and
cardiovascular disease. Almond skins are rich in polyphenols (ASP) that may contribute to
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these putative benefits. To assess their potential mechanisms of action, the in vitro effect of
ASP extracted was tested with methanol (M) or a gastrointestinal juice mimic (GI) alone or
in combination with vitamins C (VC) or E (VE) (1-10 micromol/L) on scavenging free radicals
and inducing quinone reductase (QR). Flavonoid profiles from ASP-M and -GI extracts were
different from one another. ASP-GI was more potent in scavenging HOCl and ONOO (-)
radicals than ASP-M. In contrast, ASP-M increased and ASP-GI decreased QR activity in
Hepa1c1c7 cells. Adding VC or VE to ASP produced a combination- and dose-dependent
action on radical scavenging and QR induction. In comparison to their independent actions,
ASP-M plus VC were less potent in scavenging DPPH, HOCl, ONOO (-), and O 2 (-) (*).
However, the interaction between ASP-GI plus VC promoted their radical scavenging
activity. Combining ASP-M plus VC resulted in a synergistic interaction, inducing QR activity,
but ASP-GI plus VC had an antagonistic effect. On the basis of their total phenolic content,
the measures of total antioxidant activity of ASP-M and -GI were comparable. Thus, in vitro,
ASP act as antioxidants and induce QR activity, but these actions are dependent upon their
dose, method of extraction, and interaction with antioxidant vitamins.
Diabetes improvement effects
Effect of almonds on insulin secretion and insulin resistance in nondiabetic
hyperlipidemic subjects: a randomized controlled crossover trial
Nuts appear to have a marked effect in cohort studies in reducing the risk of coronary heart
disease (CHD), but their demonstrated ability to lower cholesterol can only explain a
proportion of the reduction in risk. The aim was to assess whether improvement in
carbohydrate metabolism provides a further explanation for the effect of nuts in reducing
CHD. The effects of whole almonds, taken as snacks, were compared with the effects of low
saturated fat (<5% energy) whole-wheat muffins (control) in the therapeutic diets of
hyperlipidemic subjects. In a randomized crossover study, 27 hyperlipidemic men and
women consumed 3 isoenergetic (mean, 423 kcal/d) supplements each for 1 month.
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Supplements provided 22.2% of energy and consisted of full-dose almonds (73 +/- 3 g/d),
half-dose almonds plus half-dose muffins, and full-dose muffins. Subjects were assessed at
weeks 0, 2, and 4 and fasting blood samples were obtained. Twenty-four-hour urinary
output was collected at the end of week 4 on each treatment. Mean body weights differed
by less than 300 g between treatments. No differences were seen in baseline or treatment
values for fasting glucose, insulin, C-peptide, or insulin resistance as measured by
homeostasis model assessment of insulin resistance. However, 24-hour urinary C-peptide
output as a marker of 24-hour insulin secretion was significantly reduced on the half-and
full-dose almonds by comparison to the control after adjustment for urinary creatinine
output (P = .002 and P = .004, respectively). It was concluded that reductions in 24-hour
insulin secretion appear to be a further metabolic advantage of nuts that in the longer term
may help to explain the association of nut consumption with reduced CHD risk.
Almonds and postprandial glycemia--a dose-response study
Almonds, together with other nuts, reduce serum cholesterol levels and may reduce the risk
of coronary heart disease. There is much current interest in the relation of coronary heart
disease to postprandial events. Therefore, the effects of varying amounts of almonds were
assessed on the postprandial blood glucose response to a carbohydrate meal. The aim was
to assess the effect of adding almonds to a bread meal. Nine healthy volunteers (2 women,
7 men; mean age, 27.8 years; mean body mass index, 22.9 kg/m2) were randomly fed with 3
test meals and 2 white bread control meals on separate days. Subjects were fed the meals
after a 10- to 12-hour overnight fast. Each meal contained 50 g of available carbohydrate
from white bread eaten alone or with 30, 60, or 90 g ( approximately 1, 2, or 3 oz) of
almonds. Capillary finger-prick blood samples for glucose analysis were obtained at 0, 15,
30, 45, 60, 90, and 120 minutes. Glycemic responses were assessed by calculating the
incremental area under the 2-hour blood glucose curve. The addition of almonds to white
bread resulted in a progressive reduction in the glycemic index of the composite meal in a
dose-dependent manner for the 30-g (105.8 +/- 23.3), 60-g (63.0 +/- 9.0), and 90-g (45.2 +/5.8) doses of almonds (r = -0.524, n = 36, P = .001). It was concluded that, in addition to
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lowering serum cholesterol levels, almonds may also reduce the glycemic impact of
carbohydrate foods with which they are eaten.
Cardioprotective effect
Almonds in the diet simultaneously improve plasma alpha -tocopherol
concentrations and reduce plasma lipids
The objective of the study was to assess the dose-response effect of almond intake on
plasma and red blood cell tocopherol concentrations in healthy adults enrolled in a
randomized, crossover feeding trial. Participants were 16 healthy men and women, aged
41+/-13 years. After a 2-week run-in period, participants were fed three diets for 4 weeks
each: a control diet, a low-almond diet, and a high-almond diet, in which almonds
contributed 0%, 10%, and 20% of total energy, respectively. Changes in blood tocopherol
levels were assayed by high pressure liquid chromatography. Incorporating almonds into the
diet helped meet the revised Recommended Dietary Allowance of 15 mg/day alphatocopherol and increased lipid-adjusted plasma and red blood cell alpha-tocopherol
concentrations. A significant dose-response effect was observed between percent energy in
the diet from almonds and plasma ratio of alpha-tocopherol to total cholesterol.
Serum lipid response to the graduated enrichment of a Step I diet with
almonds: a randomized feeding trial
Frequent consumption of nuts may lower the risk of cardiovascular disease by favorably
altering serum lipid and lipoprotein concentrations. The effects of 2 amounts of almond
intake were compared with those of a National Cholesterol Education Program Step I diet
on serum lipids, lipoproteins, apolipoproteins, and glucose in healthy and mildly
hypercholesterolemic adults. In a randomized crossover design, 25 healthy subjects (14
men, 11 women) with a mean (+/- SD) age of 41 +/- 13 y were fed 3 isoenergetic diets for 4
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wk each after being fed a 2-wk run-in diet (containing 34% of energy from fat). The
experimental diets included a Step I diet, a low-almond diet, and a high-almond diet, in
which almonds contributed 0%, 10%, and 20% of total energy, respectively. Inverse relations
were observed between the percentage of energy in the diet from almonds and the
subject's total cholesterol (P value for trend < 0.001), LDL-cholesterol (P < 0.001), and
apolipoprotein B (P < 0.001) concentrations and the ratios of LDL to HDL cholesterol (P <
0.001) and of apolipoprotein B to apolipoprotein A (P < 0.001). Compared with the Step I
diet, the high-almond diet reduced total cholesterol (0.24 mmol/L or 4.4%; P = 0.001), LDL
cholesterol (0.26 mmol/L or 7.0%; P < 0.001), and apolipoprotein B (6.6 mg/dL or 6.6%; P <
0.001); increased HDL cholesterol (0.02 mmol/L or 1.7%; P = 0.08); and decreased the ratio
of LDL to HDL cholesterol (8.8%; P < 0.001). As concluded by the results, isoenergetic
incorporation of approximately 68 g of almonds (20% of energy) into an 8368-kJ (2000-kcal)
Step I diet markedly improved the serum lipid profile of healthy and mildly
hypercholesterolemic adults. Total and LDL-cholesterol concentrations declined with
progressively higher intakes of almonds, which suggests a dose-response relation.
4. References
J Agric Food Chem. 2006 Jan 25;54(2):312-8.Antioxidant polyphenols in almond and its
coproducts.Wijeratne SS, Abou-Zaid MM, Shahidi F.Department of Biochemistry, Memorial
University of Newfoundland, St. John's, Newfoundland A1B3X9, Canada.
Complement Ther Clin Pract. 2010 Feb;16(1):10-2. Epub 2009 Jul 15.The uses and properties
of almond oil.Ahmad Z.Plastic and Reconstructive Surgery, Salisbury General Hospital,
Salisbury, Wiltshire, UK.
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J Agric Food Chem. 2008 Jun 25;56(12):4427-34. Epub 2008 May 31.In vitro activity of
almond skin polyphenols for scavenging free radicals and inducing quinone reductase.Chen
CY, Blumberg JB.Antioxidants Research Laboratory, Jean Mayer United States Department of
Agriculture (USDA) Human Nutrition Research Center on Aging, Tufts University, 711
Washington Street, Boston, Massachusetts 02111, USA.
Metabolism. 2008 Jul;57(7):882-7.Effect of almonds on insulin secretion and insulin
resistance in nondiabetic hyperlipidemic subjects: a randomized controlled crossover
trial.Jenkins DJ, Kendall CW, Marchie A, Josse AR, Nguyen TH, Faulkner DA, Lapsley KG,
Singer W.Clinical Nutrition and Risk Factor Modification Center, St Michael's Hospital,
Toronto, Ontario, Canada M5C 2T2.
Metabolism. 2007 Mar;56(3):400-4.Almonds and postprandial glycemia--a dose-response
study.Josse AR, Kendall CW, Augustin LS, Ellis PR, Jenkins DJ.Clinical Nutrition and Risk
Factor Modification Center, St Michael's Hospital, Toronto, Ontario, Canada M5C 2T2.
J Am Diet Assoc. 2005 Mar;105(3):449-54.Almonds in the diet simultaneously improve
plasma alpha-tocopherol concentrations and reduce plasma lipids.Jambazian PR, Haddad E,
Rajaram S, Tanzman J, Sabaté J.School of Kinesiology and Nutritional Science, California
State University, Los Angeles, CA, USA.