Healthy Food & Healthy Living by Dr. Ayala

Can your diet affect skin appearance and aging?

Healthier diets are associated with fewer face wrinkles, while a diet rich in junk food and meat with earlier skin aging according to population studies. Yes, this is just a link. It might be that healthy eaters avoid the sun and protect their skin from it – excessive sun exposure ages the skin. Health conscious people also tend to avoid smoking, another known skin-aging factor.

Does food affect facial wrinkles?

A pilot study conducted at the UC Davis Dermatology Clinic that actually tests the effects of foods in a controlled setting does so with almonds. Participants (28 postmenopausal women with fair skin that tends to burn and freckle in the sun) were treated with 2 ounces of almonds daily for 16 weeks, and skin assessment was done using high resolution photos, and a computer based validated facial modeling measurement.

The almond group had decreased wrinkles after 16 weeks.

This prospective randomized pilot study was extended and expanded to 24 weeks. This time about 50 women completed the study.

The second study showed that at 24 weeks there was continued reduction of observed wrinkles, there was also reduced pigment intensity in the almond group, compared to the control (pigmentation is another sign of skin aging).

What is it in almonds that can affect the skin? Almonds are rich in vitamin E, an antioxidant that protects from ultraviolet rays that age the skin (UVA). Many nutrients affect skin health: antioxidants and carotenoids such as beta carotene prevent collagen degradation, and provide protection from ultraviolet radiation on the cellular level.

And although this study was performed with almonds, there’s likely nothing unique about these nuts: many healthy foods contain beneficial antioxidants that may reduce wrinkles and improve skin’s appearance. 

A prospective study feeding women 85 grams (~3 ounces) of mango daily for 16 weeks showed a reduction in wrinkling when assessed by photographs. Interestingly, consuming 250 grams (~9 ounces) of mango daily increased wrinkles after 16 weeks. The researches suggest that this unexpected result may be due to the high sugar intake associated with eating high amounts of mango.

Eat well for rosy, clear skin

A skin change that’s clearly connected with food is its pigmentation. 

Skin’s pigment changes after sun exposure: most of us tan when exposed to the sun, by the production of melanin. Skin’s color also changes by the pigments we ingest, mainly due to carotenoids found in carrots, sweet potatoes, dark green leafy greens, sweet red peppers and other colorful fruits and veggies. 

The skin tone associated with eating a carotene-rich diet is deemed more attractive and vibrant in experimental studies.

A study following 35 students for 6 weeks looked at how fruit and veggie intake affects skin tone, as measured by a spectrophotometer. The researchers found that measured skin tone correlated with reported changes in the diet: eating more fruits and veggies increased skin redness and yellowness, and these skin tone changes were achieved with about 4 servings of fruits and veggies.

What we eat, unsurprisingly, affects our wellbeing, and several skin disorders can also benefit from improving the diet. Take acne, one of the most common skin complaints, with 80-90 percent of US teens with some degree of acne. Recent research connects the Western diet – high in processed foods, sugars and animal products, low in plant and whole foods – with acne prevalence and severity.

There are countless reasons to eat more fruits, vegetables and nuts, but if you need yet another compelling one: Good food may give you beauty from within, and is probably at least as effective as some of the expensive creams in the market that promise to do so.

Dr. Ayala

Does when and how you exercise affect your appetite?

Exercise is a cornerstone of wellness, and is independently important. Exercise is also used as a tool to control weight, but it isn’t a very effective weight loss plan when applied without a weight-loss diet. Exercise’s less than expected influence on weight loss is attributed to our body’s tendency to compensate for energy loss by increasing appetite and intake, or energy conservation and a reduction in energy expenditure. But although exercise by itself (without calorie control) doesn’t result in significant weight loss, regular exercise is linked with lower risk of gaining weight over the years. 

Does when you exercise matter?

Does the timing of exercise matter? The study of our circadian rhythm – our internal clocks that run a ~24 hour cycle related to the sun’s activity – is showing that many of our processes, including hormonal secretion, appetite, and metabolic pathways, fluctuate with the time of day. 

A new study in the current issue of the journal Appetite looks at the effect of morning vs. evening exercise on appetite, food intake and voluntary performance.

The healthy volunteers undertook two trials, in one they exercised at 10:30 am, and in the other at 10:30 pm. They ate a standardized meal 2 hours before exercise (intense cycling), and were offered a meal after exercise in which they could eat as much as they wished.

And the results: Although the participants reported similar appetite regardless of the time of day they exercised, they ate on average 150 calories more when they exercised in the evening.

This is a small study, and bear in mind that many people, especially in the US and in Europe, tend to eat more food in the evening as it is. Also, when to exercise isn’t necessarily a choice – time constraints arise throughout the day, and it’s hard enough to fit exercise as it is.

If you do have the flexibility you can experiment with timing your exercise and seeing if it helps you better control your appetite and intake. 

High or low intensity

Another method that could supposedly help with appetite control through exercise is increasing the intensity of the workout. High intensity exercise may suppress hunger more than low intensity exercise.

High intensity interval training – short intermissions of high effort sprints, interspersed with recovery periods – is rising in popularity and is sold as a time-saving and more efficient way to train than moderate intensity continuous exercise.

A new review study in Appetite collected 13 randomized controlled studies compares high and medium intensity exercise.

The researchers found that both types of exercise suppressed appetite for a period of about ½- 1½  hours, high intensity exercise to a greater extent. Which makes sense: during times of acute exercise the body diverts its resources to muscles, and puts the digestive system on hold. We also know that appetite hormones like ghrelin are suppressed during exercise.

The diminished appetite does not last however. Hunger bounces back and the post-exercise disinterest in food is short lived, regardless of exercise intensity.

The habit you can keep

The most important thing is to exercise – time and type of exercise matter less – and even if there’s no effect on weight whatsoever.

The best exercise is the one you can do, the activity that you enjoy, that’s accessible to you, that fits your schedule, that doesn’t cause you discomfort, the one that doesn’t require equipment you don’t readily have or an ill-afforded membership. 

If you still haven’t mastered an exercise habit the most important parameter is sustainability – pick a plan that you could keep and adopt as second nature, one that you can stick to.

To an active and healthy 2023!

Dr. Ayala