Strengthen Your Skin’s Defense: A New Skin Health Study

Here’s another reason to crunch on: new research shows that almonds may play a supporting role in defending the skin against damage from UVB rays. Avoiding prolonged sun exposure, wearing protective clothing and using topical sunscreen are key strategies to protect against photodamage, but research suggests that what we eat may also play a role in strengthening the skin’s defenses.

What you snack on may help protect your skin

More and more, scientists are learning how dietary choices may benefit skin health and appearance, confirming the adage that you are what you eat. As the body’s largest organ system, your skin is the first line of defense against the outside world.

Recent research from the University of California Los Angeles (UCLA)¹ suggests that regular almond snacking may be one way to help strengthen your skin from within and support a sun-protective skincare routine.

How can almonds help provide UVB protection?

Here’s what lead researcher Zhaoping Li and her team found:

Study Participants:

Participants included 29 Asian women (18 to 45 years old) with skin types that ranged from “burns and does not tan easily” to “burns a little and tans easily,” technically classified as Fitzpatrick skin types II, III or IV.

Study Design:

Women were randomly assigned to one of two groups for a 12-week period:

• Almond Group: Ate 1.55 ounces (42 grams, 246 calories) of almonds daily
• Pretzel Group: Ate 1.8 ounces (51 grams, 200 calories) of pretzels daily

The researchers measured each person’s skin response to UVB rays – the type of rays known to cause sunburn – at the beginning and end of the study by measuring their individual minimal erythema dose (MED). MED is the lowest dose of UVB light needed to cause slight skin reddening to a specific site on the skin. (In this case, inner-arm skin was chosen because it has little exposure to the sun.) Skin reddening is the first indication of skin photodamage, so increased MED indicates improved protection against (or resistance to) UVB photodamage.

Study Results:

At the beginning of the study, researchers investigated several skin measures and found there were no differences in MED between groups. After the 12-week intervention:

• There was an increase in both MED (~20%) and exposure time to reach minimal reddening for women in the almond group compared to the pretzel group.No statistically significant changes in MED or exposure time were observed in the pretzel group.
• No differences in skin texture, sebum and hydration were seen in these measures over time or between groups.

While the first lines of defense against UVB exposure (like wearing protective clothing and using topical sunscreen) are external, this clinical study shows that eating almonds may be one way to support your skin from within.

The Future of Almonds and Skin Health

Previous research has investigated how eating almonds may impact wrinkles and skin pigmentation. This study on effects of UVB rays expands the body of research on skin health and almonds, with more studies planned to investigate this exciting area of research.

Why Are Almonds Your Skin’s Best Friend?

Almonds are a whole food with numerous nutrients, several of which are linked to skin health. Although the mechanism for the improvement in UV resistance among the almond eaters as seen in this study is unknown, the researchers speculate that “good” mono- and polyunsaturated fatty acids, vitamin E, quercetin (a flavonoid), and other phenolic and polyphenolic compounds found in almonds may be responsible for the increased photoprotection against UVB light¹. Here’s a list of the skin-friendly nutrients you get in a one ounce healthy handful of almonds:

60% NRV Vitamin E – an antioxidant that may help protect cells from the damaging effects of free radicals caused by pollution, UV rays from the sun, cigarette smoke and other environmental and intrinsic factors

31% NRV copper, which plays a role in skin and hair pigmentation

24% NRV riboflavin and 7% NRV niacin, two B vitamins that contribute to the maintenance of normal skin

9% NRV zinc, which contributes to the maintenance of skin

The Study: Twenty-nine Asian women (18 to 45 years old) with skin types that ranged from “burns and does not tan easily” to “burns a little and tans easily,” technically classified as Fitzpatrick skin types II, III or IV were randomly assigned to an intervention or control group in this 12-week trial. Women in the almond group ate 1.55 ounces (42 grams, 246 calories) of almonds daily while women in the control group ate 1.8 ounces (51 grams, 200 calories) of pretzels daily.

The researchers measured each person’s skin response to UVB rays – the type of rays known to cause sunburn - at the beginning and end of the study by quantifying their individual minimal erythema dose (MED). MED is the lowest dose of UVB light needed to cause slight skin reddening to a specific site on the skin. (In this case, inner-arm skin was chosen because it has little exposure to the sun.) Skin reddening is the first indication of skin photodamage, so increased MED indicates improved protection against (or resistance to) UVB photodamage.

Results:

• For the almond group, there was a significant increase in MED and in exposure time required to induce erythema at the final visit (12 weeks) compared to the start of the intervention (baseline) (p=.006). Further, the increase in MED in the almond group was statistically different compared to the pretzel group.
• For the women who consumed almonds, there was an increase in MED from 415±64 to 487±59 (18.7±19.2 % ,p+0.006) from baseline to week 12 compared to women in the pretzel group from 415±67 to 421±67 (1.8±11.1%).The exposure time to reach minimal erythema (redness) was also increased significantly in the almond group from 160±23 to 187±25 (17.5±22.2%) compared to the pretzel group from 165±27 to 166±25 (1.7±14%) (p=0.026).
• At baseline, the groups had no significant differences of MED, which indicated the change in MED was due to the almond intervention. Increased MED and exposure mean that a higher dose of UVB light was required to induce erythema (redness) after 12 weeks compared to the pretzel group.
• There were no significant differences between the two groups in their ratings of erythema or Allergan Skin Roughness by dermatologists’ assessment.
• There were no significant differences in melanin index, sebum hydration or erythema by cutometer reading.
• The mechanism for the improvement in UV resistance with the almond intervention is currently unknown. The researchers speculate that the nutrients in almonds (mono- and polyunsaturated fatty acids, vitamin E, quercetin (a flavonoid), and other phenolic and polyphenolic compounds, may improve the antioxidant and anti-inflammatory capacity of human skin, which could be responsible for the increased photoprotection against UVB light.

Study Limitations: A smaller study population was included than originally planned, due to the exclusion of those participants found to be UVB resistant at the dose and exposure time selected. This study did not investigate the effect of sunlight exposure in general nor UVA exposure; findings are limited to protection against UVB radiation. This study also investigated a younger population. Further research is needed to investigate the effects of almond consumption for older subjects with moderate-to-severe photoaged skin and for other Fitzpatrick skin types.

Conclusion: A daily snack of almonds (1.5 ounces, 42 grams) improved UVB resistance in young Asian women who consumed almonds for 12 weeks. The results suggest that including almonds in the diet may help support the skin’s internal defenses against UVB light.