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Lifestyle and ageing

nutrition2Lifestyle and ageing

By cutting out the healthy fats needed for optimal skin function, many low-fat diets can cause accelerated skin ageing. In the first of a two-part series, Dr Stefanie Williams investigates the effects of diet on skin ageing processes, particularly oxidative stress, glycation and inflammation

 

Our desire to look young has deep evolutionary roots, as scientific evidence confirms a connection between inner health and outer youthfulness. Perceived age has been proven in studies to be a good estimate of general health. It has also been shown that the younger we look, the more likely we are to live a long life.

However, things we do or are unknowingly exposed to on a daily basis may speed up the ageing process and diminish the chance of reaching our full age potential. Lifestyle choices have a significant influence on how well our skin ages. Well known lifestyle habits with negative influence on skin ageing are smoking and excessive sun exposure.

More recently, urban pollution has gained increasing interest. However, one greatly underestimated lifestyle aspect with influence on skin ageing is diet.

But beliefs are changing and what has been considered a ‘healthy’ diet over the last 30 years—namely low-fat, high-carbohydrate eating—might be ageing our skin much quicker than need be!

 

Oxidative stress 

Oxidative stress and inadequate clearance of material damaged in the process is acknowledged as one of the key mechanisms in ageing; not only in our skin, but in all major systems of our body. One of the main aims of any anti-ageing strategy, therefore, should be to reduce free radical production and increase antioxidant levels in the body and skin.

Studies have confirmed that good dietary habits are a major determinant of our body’s antioxidant status and oxidative stress level. We can raise our internal antioxidant levels significantly by eating antioxidant rich foods such as vegetables.

An interesting skin study by Nagata et al confirmed that a greater intake of green and yellow vegetables is associated with decreased skin wrinkling in the crow’s feet area. Another study revealed that increased vegetable and fruit intake benefits our skin colouration in a way that makes us look more attractive to other people. This had an even greater impact than tanning.

Most intriguingly, there are now several studies which clearly show that high vegetable consumption is associated with longer telomeres, and therefore lower biological age.

 

Glycation 

Glycation is also a very important mechanism of ageing. It refers to a process where sugar molecules such as glucose and fructose attach themselves to other molecules in our body, including collagen in our skin, to form tissue-harming cross-links called advanced glycation end products (AGEs). These cross-links prevent collagen from performing its optimal function as a major supporting structure in our skin. Glycation also causes other destructive reactions in our skin, including free radical formation, oxidative stress and inflammation, all of which accelerate ageing.

Each of these changes creates an environment that supports degradation of collagen and compromises integrity and regeneration of our skin. Some degree of glycation occurs all the time—which is fine—but the extent of glycation in our skin is greatly increased by consuming a high sugar diet.

We can significantly reduce the rate of glycation by reducing the amount of sugary foods we eat on a daily basis. It’s worth noting that fructose, such as Agave syrup, is even more active in generating AGEs than conventional sugar.

Interestingly, glycation in our skin is increased after excessive sun exposure. Another study confirmed that long-standing hyperglycemia impairs skin barrier function including protection against bacteria.

The same study also confirmed accelerated skin ageing in people with high blood sugar levels.

Not surprisingly, the acceleration of skin ageing processes was found to be in direct proportion to the duration of hyperglycaemia. High blood sugar levels have also been shown to reduce growth factor release including human growth hormone (HGH), which has skin-rejuvenating properties.

A scientific study confirmed that higher blood sugar levels correlate with higher perceived ages. In other words, people with higher blood sugar look older. It is also known that familial longevity is associated with better blood sugar control.

 

Sugar storage

The message to reduce sugar consumption is something the media are increasingly catching onto. However, an often-neglected fact is that carbohydrates in starch (amylose and amylopectin) are simply long strings of sugar molecules. Starch is essentially nature’s storage form of sugar.

After eating starchy carbohydrates such as bread, pasta, rice or potatoes, our body ultimately breaks these linear or branched sugar strings down into individual sugar units. Eventually every 4g of starchy carbohydrates will result in one teaspoon of sugar in our blood.

Most starches do this at a slower pace than sugar. But some, like cornflakes breakfast cereal or a plain baguette—and even supposedly healthy foods such as roast parsnip or baked potato—can have a worse effect on our blood sugar level than pure table sugar. That’s why a diet relying largely on easily digestible, processed carbohydrates is disadvantageous for long-term skin health and our longevity.

In addition to AGEs being generated in our skin, there are also preformed AGEs present in many of the foods we consume on a daily basis. The exact levels depend on the type of food and how it is prepared. Processed foods generally contain higher contents of preformed AGEs than natural foods.

Most of the pre-packaged, processed food in supermarkets also contain many other unwelcome sugars in various forms—soy protein, modified starches and unstable polyunsaturated vegetable oils—so are best avoided in favour of natural, unprocessed foods.

 

Inflammation 

As nature intended, acute inflammation with redness, heat and swelling can be a useful process for our body. However, too much of a good thing can become a bad thing, and that’s clearly the case with chronic inflammation. In today’s world, bad dietary habits and other modern lifestyle aspects such as chronic stress can lead to low-grade, chronic inflammation.

A number of factors can contribute this condition, including high blood sugar and insulin levels, and oxidative stress. This invisible form of inflammation smoulders silently in the body, often for decades without obvious symptoms. However, all along it accelerates ageing.

As we age, our skin is unable to produce important proteins such as collagen and elastin as well as it used to. To make matters worse, it also degrades them quicker via group of enzymes called matrix-metallo-proteinases (MMPs).

Certain environmental and lifestyle factors further induce MMPs in our skin. The more oxidative stress and inflammation we have in our skin, the higher the rate of collagen and elastin degradation.

 

Telomere length 

Telomeres maintain the integrity and stability of our genetic material by protecting our chromosomes. Every time a cell divides, the telomere takes the brunt and shortens a little to protect the vital genetic information between them. Therefore telomere length is an important piece of information when judging our ‘real’ cell age, as opposed to our chronological age.

Shorter telomeres have been linked to increased cancer risk and even a shortened life span. Skin cells have been described as being particularly susceptible to accelerated telomere shortening because of their high proliferation rate and exposure to DNA-damaging influences such as oxidative stress.

However, we now know that telomere shortening can happen at different rates and that we can influence the rate of telomere shortening with our lifestyle choices.

Telomere shortening and consequent cell ageing is accelerated by any sort of cellular stress. The more free radicals that are present in our tissues and the greater the oxidative stress our cells are exposed to, the faster our telomeres shorten. High levels of blood sugar, low-grade inflammation and obesity have also all been linked to telomere shortening. Positive lifestyle interventions, on the other hand, are able to improve telomere length.

 

Ageing hormones 

The sugar-regulating hormone insulin, secreted in the beta cells of our pancreas, is one of our pro-ageing hormones. While insulin is our friend at optimal levels, clearing away excess sugar from the blood stream, excess insulin release has been shown to contribute to free radical generation, oxidative stress, inflammation and striking acceleration of skin ageing.

Insulin also interferes with other hormones. For example, it leads to a decrease in the levels of testosterone, didehydroepiandrosterone (DHEA) and other anti-ageing sex hormones, which are known to decline with age. Insulin also increases the level of sex-hormone-binding-globulins, which keep sex hormones bound and therefore inactive.

Not all the effects of insulin are so subtle. After a high carbohydrate meal, there is an insulin spike, making our blood sugar level plummet a couple of hours later and leaving us ravenous for more sugar and other carbohydrates.

Giving in to the renewed hunger creates a vicious circle, leading to fluctuating high and low blood sugar levels throughout the day.

The repeated ups and downs of glucose and insulin are very stressful for our body. It responds by releasing pro-ageing stress hormones such as cortisol, which encourage collagen breakdown.

Eventually, these continuous waves of sugar intake, blood sugar spikes and insulin hikes will make our cells less responsive to insulin, thereby creating ‘insulin resistence’. A good sensitivity of our cells to insulin, however, is very important for optimum ageing and superior insulin sensitivity has been connected to familial longevity.

A typical Western diet is often highly insulinaemic and with low-fat, high sugar and starch eating habits, insulin greatly accelerates the skin’s ageing process. We should try and moderate our insulin secretion for optimal anti-ageing benefits. Measures include avoiding sugar-containing foods and cutting down on foods that are broken down into sugar molecules in your body.

 

Building blocks 

Protein provides crucial building blocks for our body and forms muscle, hair, skin and connective tissue. As some amino acids are essential—the body can’t produce them itself—we need to ensure we ingest complete protein with our food. As our body has little capacity to store protein, we should provide it with sufficient amounts on a daily basis.

We also need to forget the low-fat brainwashing of the past 30 years. Our body and skin need fat. Lipids form a vital component of our cell membranes and help maintain cell structure and function. Fat is also important for optimal hormone production.

Studies confirm that higher intakes of total fat—monounsaturated and saturated—are significantly associated with increased skin elasticity and decreased wrinkling of the skin. Fat intake therefore makes our skin more elastic and less wrinkly. Therefore, consuming sufficient amounts of fat is crucial to maintaining healthy and beautiful skin as we age.

There is another reason to avoid falling into the low-fat trap. When the food industry creates a low-fat food product, the removed fat has to be replaced with something. In the vast majority of cases, refined carbohydrates are added.

Many supposedly ‘healthy’ low-fat products are stuffed with processed carbohydrates, which increase your level of insulin, glycation, oxidative stress and create chronic inflammation, all of which have an adverse effect on skin health. Healthy fats on the other hand support optimal skin function.

The consumption of chemically altered, highly processed, omega-6 rich fats such as unstable polyunsatured vegetable oils has led to all fats being viewed as a villain.

But eating good amounts of monounsaturated fats such as olive oil and avocados and saturated fats—such as coconut oil and animal fats, which are very stable and therefore suitable for cooking—is beneficial for our skin and for overall health. Olive oil’s monounsatured fats have, for example, been shown to be associated with a lower risk of severe sun-induced skin ageing in both men and women.

Omega-3 fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have also been shown to be beneficial for our skin as they are anti-inflammatory, antioxidant and help protect telomere length.

In one study, individuals in the highest omega-3 quartile experienced the slowest rate of telomere shortening. Supplementation with omega-3 rich fish oil has also been shown to support long-term skin health by preventing sun-induced changes in our skin and improving collagen metabolism.

In a study by Fortes et al, it was shown that regular consumption of fish can even be protective against melanoma skin cancer. However, we should remember that omega-3 fatty acids as polyunsaturated fatty acids are inherently unstable and need to be treated with care.

There is true hysteria surrounding saturated fats. However, they are not as evil as their reputation. They actually have many advantageous properties such as their stability.

Saturated fatty acids are an integral part of our body and constitute at least 50% of our cell membranes. They help prevent oxidative damage to cells and are an important part of cell biology, both in the skin and throughout the entire body.

Thankfully there seems to be a gradual rethinking about saturated fat intake and general health. A meta-analysis stated, “there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of cardiovascular disease”.

A British Heart Foundation funded meta-study also recently concluded, “current evidence does not clearly support cardiovascular guidelines that encourage high consumption of polyunsaturated fatty acids and low consumption of total saturated fats”. I am looking forward to further studies in this area, as for our skin saturated fats are highly beneficial.

 

Boosting cell repair 

Another interesting way to support our body and skin staying youthful is intermittent fasting (IF).

There are a variety of different approaches. One of the most popular ways is to fast for 24 hours twice per week—for example, don’t eat from dinner the previous day until dinner the next day. Many people currently do this for weight management in the UK, without realising that IF is also highly anti-ageing.

Intermittent fasting promotes healthy autophagy. Autophagy is a cellular process with which cells get rid of problematic content. This not only applies to infectious agents, but also to its own damaged, malformed or dysfunctional cell components.

Autophagy also ensures the turnover of aged cellular components. When digesting this cellular ‘junk’, the cell breaks it down into constituent parts, such as fatty acids, amino acids and sugar. These are then reused by the cell—a true recycling process.

When fewer ‘building blocks’ become available via food, such as during fasting, autophagy is increased. This means that when fasting, our cells ramp up the process of tidying up, because they are trying to find cellular ‘junk’ they can dismantle in order to obtain building blocks needed. A study confirmed that promoting autophagy can extend lifespan by as much as 50%.

IF has also been shown to increase insulin sensitivity and decrease oxidative damage. During fasting, secretion of human growth hormone—one of our ‘skin youth’ promoting hormones—also increases.

What we eat on a daily basis has a significant impact on your skin’s ageing process. The current Western low-fat obsession with over-reliance on starchy, grain-based and sugary foods, together with constant grazing throughout the day, doesn’t do our skin any favours.

With an improved way of eating, however, we are able to reduce oxidative stress, inflammation, glycation and telomere shortening, while encouraging a more youth-promoting hormonal homeostasis.

Dr Stefanie Williams is a dermatologist and medical director at European Dermatology London W: eudelo.com. Further information can be found in Dr Williams’ book “Future Proof Your Skin – Slow down your biological clock by changing the way you eat”. In the next edition of Body Language, Dr Williams will be looking at the connection between skin ageing and stress.

References

1. Anlasik T, Sies H, Griffiths HR, et al. “Dietary habits are major determinants of the plasma antioxidant status in healthy elderly subjects.” Br J Nutr. 2005; 94(5):639-42.

2. Avery NC, Bailey AJ. “The effects of the Maillard reaction on the physical properties and cell interactions of collagen.” Pathol Biol (Paris). 2006; 54(7):387-95.

3. Boukamp P. “Skin aging: a role for telomerase and telomere dynamics?” Curr Mol Med. 2005; 5(2):171-7.

4. Buckingham EM, Klingelhutz AJ. “The role of telomeres in the ageing of human skin.” Exp Dermatol. 2011; 20(4):297-302.

5. Chowdhury R, Warnakula S, Kunutsor S, et al. “Association of Dietary, Circulating, and Supplement Fatty Acids With Coronary Risk: A Systematic Review and Meta-analysis.” Ann Intern Med. 2014; 18;160(6).

6. Danby FW. “Nutrition and aging skin: sugar and glycation.” Clin Dermatol. 2010; 28(4):409-11.

7. Epel ES, Lin J, Wilhelm FH, et al. “Cell aging in relation to stress arousal and cardiovascular disease risk factors.” Psychoneuroendocrinology. 2006; 31(3):277-87.

8. Farzaneh-Far R, Lin J, Epel ES, et al. “Association of marine omega-3 fatty acid levels with telomeric aging in patients with coronary heart disease.” JAMA. 2010; 303(3):250-7.

9. Fortes C, Mastroeni S, Melchi F, et al. “A protective effect of the Mediterranean diet for cutaneous melanoma.” Int J Epidemiol. 2008; 37(5):1018-29.

10. Galluzzi L, Morselli E, Vicencio JM, et al. “Life, death and burial: multifaceted impact of autophagy.” Biochem Soc Trans. 2008; 36(Pt 5):786-90.

11. Gunn DA, de Craen AJ, Dick JL, et al. “Facial appearance reflects human familial longevity and cardiovascular disease risk in healthy individuals.” J Gerontol A Biol Sci Med Sci. 2013; 68(2):145-52.

12. Latreille J, Kesse-Guyot E, Malvy D, et al. “Dietary monounsaturated fatty acids intake and risk of skin photoaging.” PLoS One. 2012;7(9):e44490.

13. Marcon F, Siniscalchi E, Crebelli R, et al. “Diet-related telomere shortening and chromosome stability.” Mutagenesis. 2012; 27(1):49-57.

14. Mays PK, McAnulty RJ, Campa JS, Laurent GJ. “Age-related alterations in collagen and total protein metabolism determined in cultured rat dermal fibroblasts: age-related trends parallel those observed in rat skin in vivo.” Int J Biochem Cell Biol. 1995; 27(9):937-45.

15. McDaniel JC, Massey K, Nicolaou A. “Fish oil supplementation alters levels of lipid mediators of inflammation in microenvironment of acute human wounds.” Wound Repair Regen. 2011; 19(2):189-200.

16. Nagata C, Nakamura K, Wada K, et al. “Association of dietary fat, vegetables and antioxidant micronutrients with skin ageing in Japanese women.” Br J Nutr. 2010; 103(10):1493-8.

17. Noordam R, Gunn DA, Tomlin CC, et al. “High serum glucose levels are associated with a higher perceived age.” Age (Dordr). 2013; 35(1):189-95.

18. Park HY, Kim JH, Jung M, et al. “A long-standing hyperglycaemic condition impairs skin barrier by accelerating skin ageing process.” Exp Dermatol. 2011; 20(12):969-74.

19. Piccardi N, Manissier P. “Nutrition and nutritional supplementation: Impact on skin health and beauty.” Dermatoendocrinol. 2009; 1(5):271-4.

20. Pilkington SM, Massey KA, Bennett SP, et al. “Randomized controlled trial of oral omega-3 PUFA in solar-simulated radiation-induced suppression of human cutaneous immune responses.” Am J Clin Nutr. 2013; 97(3):646-52.

21. Polidori MC, Praticó D, Mangialasche F, et al. “High fruit and vegetable intake is positively correlated with antioxidant status and cognitive performance in healthy subjects.” J Alzheimers Dis. 2009; 17(4):921-7.

22. Schalkwijk CG, Stehouwer CD, van Hinsbergh VW. “Fructose-mediated non-enzymatic glycation: sweet coupling or bad modification.” Diabetes Metab Res Rev. 2004; 20(5):369-82.

23. Shen J, Terry MB, Gurvich I, et al. “Short telomere length and breast cancer risk: a study in sister sets.” Cancer Res. 2007; 67(11):5538-44.

24. Siri-Tarino PW, Sun Q, Hu FB, Krauss RM. “Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease.” Am J Clin Nutr. 2010; 91(3):535-46.

25. Tiainen AM, Männistö S, Blomstedt PA, et al. “Leukocyte telomere length and its relation to food and nutrient intake in an elderly population.” Eur J Clin Nutr. 2012; 66(12):1290-4.

26. Vellai T. “Autophagy genes and ageing.” Cell Death Differ. 2009; 16(1):94-102.

Author: bodylanguage

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