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Food is information

Our culinary journey through food in medicine could not be complete without visiting the topic of how food and lifestyle affect the very foundations of our existence.

Genes, made up of DNA, are what we inherit from our parents. They are the molecular code for characteristics such as how we look, the likelihood that we will get a chronic disease and even our behavioural traits. They also regulate intricate processes in the body, such as how we deal with inflammation and remove cancer cells. Vitamins and minerals, as well as things such as sleep quality and stress, can all impact the factors that alter the expression of our genes for better, or worse, health.

What has this got to do with food? Everything.

Micronutrition and the timing of when we eat as can alter our gene expression.^71,72 Our food is constantly communicating with our DNA.

This area of research is adding yet another layer of complexity to the scientific study of why and how what we eat affects our health. There is a wealth of information available on this subject far beyond the remit of this cookbook! If you are interested, I have extra information on my website, www.thedoctorskitchen.com, including links to reading materials on subjects such as nutrigenomics, nutrigenetics and epigenetics.

Despite its complexity, I included this section because I want you to appreciate the incredible effect food has on our longevity. I want to share some insight into the fascinating studies that have framed my understanding of how food has positive effects on our bodies.^73,74 It explains why I try to weave certain ingredients into my dishes that tick the boxes for both flavour and function. By including these delicious ingredients in our diet we can potentially affect our genetic functioning for the better.⁷⁵ Today, we can start this colourful and enjoyable journey toward good health.

I hope this motivates and inspires you to look at adapting your diet as a powerful, positive intervention. On a personal note, learning more about this field of study encouraged me to increase my intake of certain foods and explore lifestyle practices that may improve the functioning of my body. I believe that if we focus on wellness and introducing health-promoting foods and activities, the body has incredible potential to look after itself, as has been my personal experience. It’s so empowering to know that despite our genes, we have the ability to steer the direction of our destiny using lifestyle.^71,76 Food is integral to this process. It is the cornerstone of healthcare and one of the biggest joys in life.

So, what do we need to eat to improve our gene functioning? In a very general sense, ensuring we have a variety of micronutrients (vitamins and minerals) is the best way to ensure proper functioning of our cells and expression of our genes. Our understanding is still basic and there’s a long road ahead, but there are some key diet and lifestyle measures that we can all incorporate to ensure the correct functioning of our bodies. The good news is, these micronutrient-dense foods are tasty, cheap and easy to cook with. Here are some examples of foods I encourage my patients to eat regularly, and a snapshot of the science that explains why.

+ A WORD OF WARNING

Already, there are tools you can buy that can read your genetic profile and claim to give you tailored nutrition advice online, but I suggest treating these with caution. Simply looking at genetic profiling in isolation is a narrow perspective to take and it’s not as simple as ‘eating to beat your genes’. Health outcomes are the result of a complex interplay of food, gut health, environmental stressors and many other variables. The future of medicine is definitely personal⁷⁷ and I’m certain it will soon become the norm to have these tests, but they have to be taken in the context of the individual’s circumstances. We are sophisticated machines with multiple pathways beyond our genes that we need to consider, but it doesn’t stop me from getting excited about the future application of these tools for practitioners.

Greens for your genes

Romanesco cauliflower, cabbages of all kinds, pak choy, rocket leaves, broccoli, broccoli sprouts, Brussels sprouts, cavolo nero, kale, chard…

Everyone knows that these greens are ‘good for us’. It has been drilled into our heads since childhood. But, apart from fibre and vitamins, greens have a wealth of other properties. Cruciferous vegetables (also known as brassicas), in particular, are known for their sulforaphane content. Sulforaphane is a plant chemical currently being researched for its ability to stabilise cells and protect against cancer. It also appears to impact a master regulator of genes involved in reducing cancer activity.⁷⁸

But this is merely one of the hundreds of compounds involved in the mechanism of why greens are ‘good for us’. Cauliflower, broccoli, broccoli sprouts and rocket leaves all contain sulforaphane, plus a whole lot more that hasn’t yet been fully investigated. And these vegetables don’t just contain novel chemicals; they are also full of micronutrients like magnesium and folate which are vital for repairing and producing DNA.^79,80

One of the key features of the influential Dean Ornish study⁷³ that showed lifestyle changes could promote genes that fight cancer, was a plant-focused diet high in cruciferous vegetables. Best of all, these ingredients can taste wonderful with the right spices, herbs and cooking techniques to moderate their naturally bitter taste. You’ll want to have these affordable foods every day.

Spice your DNA

Herbs and spices are what make cooking and eating so pleasurable. In Middle Eastern cuisines, they often serve fresh herbs alongside tagines and stews to complement the rich, earthy flavours. Vietnamese food is commonly presented with a side plate brimming with mint leaves and whole coriander stems. Our Indian version of a salad (see here) includes sliced red onion, fresh lemons and, of course, raw chilli. As a child, I would watch in awe as my father ate small bites of whole green chilli with his meals. I still haven’t quite acquired the taste for this level of heat!

Fresh leaves are more than just sharp flavour notes to accompany a meal. Simple herbs like parsley, for example, contain plant chemicals called flavones.⁸¹ These are known to promote the activity of genes that are responsible for suppressing inflammation,^82,83 a key feature in conditions like cancer and diabetes.

And it’s not just parsley … rosemary, turmeric, ginger, oregano, onion and garlic are also abundant with health-promoting chemicals including epigalletins, quercetin, luteolin and others with equally long and confusing names.⁸⁴ To cover just our limited knowledge of all these compounds and their potential uses would fill volumes of books.

I don’t want to steer you in the direction of only eating particular foods to alter your gene activity – I simply want you to appreciate the immense power of everyday ingredients. Herbs and spices are very much part of that line-up. So, when you look at my recipes, notice how highly flavoured and spiced they are. There is a method behind these flavour-packed dishes.

Colour your plate

I’m passionate about colours. They truly represent the complexity and beauty of food. Beyond their spectacular visual display and abundance of antioxidants, colourful foods are exceptionally important for us for their effects on our genes.⁷⁵ Plant chemicals (also called phytochemicals and phytonutrients) are responsible for these beautiful pigments and are usually found concentrated in the skins of fruits and vegetables.

We know that reducing inflammation is hugely important when it comes to longevity and reducing the risk of diseases ranging from dementia to depression.⁸⁵ An example of a plant chemical that gives food a vibrant, red colour is anthocyanin.⁸⁶ You’ll find this in everything from beetroot and wild berries to red onion (not just pomegranate juice and acai powder!). Anthocyanins are known to activate the gene responsible for heightening antioxidant activity which can prevent against cancer.⁸⁷ It is an incredible ingredient, but one of literally thousands that could be just as impressive.

Rather than using a reductionist approach to the science that concentrates on the benefits of singular compounds, I implore you to remember that all foods have a number of chemicals in varying amounts that are wonderful.⁸⁸ Variety and nutrient density is the goal here. Don’t focus too much on exact lists of ingredients and their chemical attributes. Choose vibrant colours and foods that you and your family will enjoy to reap the benefits of nature’s gifts. And remember … don’t throw away the skins!

The power of your microbiome

The microbiome is a feature of our health that we’ve already visited (see here). It is the name we give to the trillions of microbes (mostly bacteria) that reside all over our body but mainly in the gut. Because of the sheer number of microbes in this population, your microbiome consists of over 100 times more genetic material than your own.⁸⁹ This population has immense impact on the health of your body and mind because the microbiome genetic code is quite literally communicating and interacting with your own.^90,91 The scientific community has only started appreciating this information over the last 20 years. The most exciting feature is that although we cannot change our own genetic information, the genes and health of our microbial population can be altered by environment and that affects the expression of our DNA.⁹²

This may all sound quite fantastical – the fact that our destiny is in our hands. We are quite far away from precision treatments that alter the microbiome for specific health outcomes, but science tells us that if we eat and live according to principles that help our microbiome population thrive, we live healthier lives and are less likely to suffer disease. One of the probable reasons for this is because the microbiome has an ability to positively affect the expression of our DNA. Nurturing your gut health (see here) could prove vital in disease prevention and treatment.

Lifestyle for genes

• Sleep is integral to health. It’s also very impactful on our microbiome and our circadian rhythms that affect our biology and gene expression.⁹³ Melatonin is a hormone (produced during adequate sleep) which activates and regulates hundreds of genes involved in repair, antioxidant function and, you guessed it, inflammation.^94,95 Sleep does far more than just let your muscles repair and brain recuperate; it’s essential for protecting you against disease. So, practise good sleep hygiene: try not to eat or use electronic stimuli two hours before bed, and sleep your way to health.

• Fasting is a practice made popular by diets like 5:2 and proponents of ‘ancestral eating’ that aim to mimic the lifestyles of former hunter-gatherer populations. While I take issue with blindly following a standard diet, fasting is a component of these regimes that may have some legs. Incorporating a fasting practice into your eating habits has been shown to improve the expression of genes that are responsible for removing oxidants that cause inflammation and turning on genes that fight cancer cells.^96,97 But fasting doesn’t need to be a tedious feat where you remove all sources of energy for a 24-hour period. I’m a fan of defining your eating period to 10–11 hours per day. For example, if you were to eat breakfast at 8am, try not to eat dinner later than 7pm. Getting into a routine where you have the same ‘defined eating period’ on a daily basis may have benefits by heightening the expression of genes that control sugar and lead to greater longevity.^98,99,97 Most of the studies also found that participants lost weight and this has obviously generated a lot of attention, but in my opinion losing weight isn’t necessarily always the goal. If we focus on introducing health-promoting habits and wonderful nutrition I am certain you will lose weight, but more importantly it will be enjoyable, safer and much better for your overall health. Wellness is the goal rather than a desired number on a set of scales.

• Mindfulness doesn’t have to be cliché. My father grew up on a farm. He would wake up before dawn every single day and in his sleepy state make the short walk to the farm where he would duly milk the cows for the family’s breakfast and butter-churning routine. This could be considered an example of mindfulness. An activity which removes thought and reason, and incorporates routine. Where the mind is quiet, restful and unstimulated.

Buddhists sweep. Beach bums surf. Commuters listen to smartphone apps. However you decide to practise it, mindfulness has never been so important as it is in now, in today’s world of excessive electronic use and hyperactivity.

We live in a perpetual state of anxiety, provoked by constant stimuli, and I believe meditation is key. One of the most impressive research studies I have come across was a small experiment looking at a group of people taught to meditate over a three-week period. Using a specific gene marker to measure the inevitable ageing process, they discovered that the meditation had improved the marker that was expected to naturally worsen.^100,101 Meditation has been hypothesised to have a literal anti-ageing effect.¹⁰² If an intervention can alter gene activity to that extent, it has a place as a ‘medicine’ in my opinion. So, decide on your meditative strategy and practise it for at least 10–20 minutes each day. You should find it has a calming effect on your mood, even if we can’t conclusively prove its effect on wrinkles.

We live in a perpetual state of anxiety, provoked by constant stimuli, and I believe meditation is key.