Part 6 – The DNAfit genetic test

Over the last few posts, we have learned how genetic variations between us make us the individuals we are, both on the inside and on the outside. We know that food speaks to our genes and in turn, our genes can affect how our foods are processed. We understand that knowing our genetic differences can help us to exercise more efficiently and maintain a healthy weight. And we know that we can help our genes stay healthy as we age.

We now appreciate that we have more influence and control over our protein-encoding genes than we realised. Thankfully, we can positively influence our genetic health trajectory. The more ‘inside knowledge’ of your personal genetic make-up you have, the better you can tweak your diet, lifestyle and training, to optimise your health.

During March 2019, I am offering the complete ‘DNAFit Diet Fitness Pro 360’ package at a 35% discounted rate, down from £179 to just £119 inclusive of VAT. You will receive an easy-to-understand, full colour report which you can access via an online through the DNAfit website. I have also secured for you, complimentary 3-month access to a personalised diet, meal planner and fitness planner, again accessible online.

Your report will tell you:

Nutrition-specific predispositions

Screenshot 2019-03-19 at 11.19.43

Your recommended diet – Mediterranean, low fat or low carbohydrate and the best proportion of macronutrients to eat

Carbohydrate sensitivity – The amount and types of carbohydrates to eat to help you to understand and manage your cravings and weight. It will tell you if you need to follow a low carbohydrate diet, a reduced fat diet, or a Mediterranean diet.

Saturated fat sensitivity – How many and which types of fats you should be eating for weight loss, lowered inflammation and for good general health.

Lactose intolerance – Some of us are born with an inability to break down lactose, many others acquire it as we age. Find out if dairy is a healthy option for you, or not.

Coeliac predisposition – Coeliac disease develops in approximately 30% of the population, which carry this genetic variant. This test will identify your susceptibility. (Note-coeliac disease is only diagnosed from a blood test done by your GP).

Caffeine sensitivity – Find out if you are classified as a “fast” or “slow” metaboliser of caffeine, and therefore the optimal amount to consume.

Liver Detoxification ability – Find out if you need to eat more cruciferous vegetables to support better liver detoxification function.

Methylation cycle and B-vitamin need– Find out if you need more vitamin B6, B9 (folate) and B12 to keep your methylation cycle working efficiently.

Vitamin D need – Find out if you need above the daily recommended allowance, based on your genetics.

Anti-oxidant needs – Learn which anti-oxidants are key for you and in what quantities.

Inflammation predisposition– Learn your genetic vulnerability to inflammation to guide you to eat more anti-inflammatory foods, improve your sleep and maintain regular exercise.

Salt and alcohol sensitivity– Learn how much salt and alcohol it is best for you to consume for optimum health.

Stress sensitivity– learn if you are a natural “worrier” or “warrior” and what you can do to help yourself handle stress better.

Fitness-related predispositions

Power versus endurance profile – Know your genes that influence power or endurance activities and learn how to train to your genetic strengths.

Aerobic potential – Understand your “potential” (not actual) VO2 max for endurance sport.

Recovery speed – Understand what your genes tell you about your natural recovery speed and how to plan your exercise schedule accordingly.

Recovery needs – Learn about your body’s need for vitamins and micronutrients to optimise your recovery after training.

Injury risk – Some people are genetically at more risk of injury than others. Learn where you are on the injury risk scale and what you can do about it.

How to get your test kit

Please contact me directly. I will send you an email outlining the administration and then send you the test kit in the post. You will take a cheek-swab at home and send it off in the box provided. It’s very easy and the instructions are simple and clear. 10-14 days later, you will receive a full-colour report, grouped into two sections, your nutrient predispositions and recommendations and your exercise predispositions and recommendations.

DNAFit is a Queens Award-winning global genetics company 2018 and shortlisted for BT Sports Industry Awards 2018. DNAfit has been used by Olympians like Craig Pickering, Andrew Steel and others like Mo Salah.

Fiona Golfar, Editor-at-large at Vogue UK said, “Impressively, in just over a week following my recommendations, I went down a clothes size, which convinces me that knowing your body’s needs at a genetic advantage is a huge leap forwards”.

The Today Show reported, “Massive increase in everything. These are the kinds of gains you can get when you work with your genetics and not against them.”

I hope that you have enjoyed reading this mini-series about nutrigenetics and nutrigenomics, and I hope you are keen to delve more deeply into what your own personal genetics are telling you so that you can improve your health as a consequence.

I wish you good health and happiness,

Dawn

Part 5 – Optimising healthy ageing

So how do we help our genes continue to work well as we age? How can we prevent DNA damage? Let’s take a look at three diet and lifestyle factors you can optimise to support healthy genetic ageing – micronutrients, inflammation and stress.

Micronutrients and DNA Health

Micronutrients such as vitamins and minerals play key roles in the making and repairing of DNA. Too much, or not enough, micronutrients can cause nicks and breaks in the DNA bonds. If the cell doesn’t have enough key micronutrients, then it can’t make the right proteins to repair itself. This can lead to mutations. There is a developing body of research which links DNA damage to infertility, cancer, cardiovascular disease, neurodevelopmental disease, cognitive decline and risk of early death.

Key micronutrients for making, repairing, and keeping DNA working well are:

  • Polyphenols (natural beneficial chemicals in plants)
  • The antioxidant vitamins A & C
  • B2, B3, B6, B9, B12
  • Zinc & iron
  • Magnesium & calcium
  • Manganese & selenium

We can get all of these from a diet rich in deeply-coloured fruits and vegetables, lots of dark green leafy vegetables, lean high-quality meat and fish, unprocessed whole grains, legumes, nuts, seeds and healthy fats and oils. For those of us who don’t, or can’t, eat enough of these foods, supplements may be an option.

If you are thinking of taking supplements it is best to do it under professional guidance, otherwise you might just be wasting your money on ineffective supplements that are not the right fit for you. Where possible, get your nutrient levels tested first. Feel free to ask me if you need any help or guidance with that. Then order a genetic test to learn your genetic predispositions for key micronutrients. Then, you can use both specific foods and supplements to make up for any shortfalls and reduce your risk of the problems that deficiencies can cause to your health.

Healthy ageing depends on good ‘methylation’, which is a biochemical detoxification process that happens in every cell, all the time. Vitamin B6, folate (B9) and B12 are all needed to keep the methylation cycle working efficiently and prevent the cells normal toxic waste products from building up. This detoxification process requires a protein-encoding gene called the MTHFR gene to make an enzyme to convert dietary folate (B9) into active methyl-folate. There are common genetic variations (SNPs) within the MTHFR gene, which can slow the function of this enzyme by up to 30-40%. If you have this variation there are plenty of dietary and lifestyle changes you can make to help yourself. For example, eat lots more green leafy vegetables and other foods high in folate such as eggs, asparagus, beetroots, citrus fruit and Brussel Sprouts. You could also add a methyl-folate and B12 supplement (but remember to test to make sure you keep within a normal range); avoid exposure to chemicals in your diet and environment (household cleaning products, body sprays, creams, pesticide residues, ultra-processed food); practice stress reduction on a daily basis and get the right amount of sleep for you.

Inflammation

Inflammation is a driver of chronic disease. Certain genes are responsible for regulating the amount of protective inflammation that our immune system creates in our body. We need a certain amount of inflammatory processes to repair cell damage, clean up dying cells, repair injuries and recover from infections. Again, it’s the balance, not too much and not too little, which is the hallmark of a healthy body. A prolonged, excessive inflammatory response is associated with many degenerative diseases, while an under-responsive immune system leaves us vulnerable to infection. We can influence our levels of inflammation in many ways, one crucial way is by eating an anti-inflammatory diet, like the Mediterranean diet.

In 2010, Bakker et al. published a paper in the American Journal of Clinical Nutrition. They studied various anti-inflammatory dietary compounds, resveratrol (found in the skins of red grapes and red wine), green tea extract, vitamin E, vitamin C, omega 3 polyunsaturated fatty acids and tomato extract. Together, they were given to overweight men who had elevated blood markers of inflammation. Researchers saw specific changes in gene expression that brought about lowered inflammation – a great result for their disease risk.

Here are some anti-inflammatory compounds you may want to increase in your diet.

Omega 3 fatty acids – Foods that contain essential omega 3 fatty acids are salmon, mackerel, herring, sardines, anchovies, trout, walnuts, flax seeds, hemp seeds and chia seeds. We all have different SNPs in the Tumor Necrosis Factor-alpha gene which influence our unique level of inflammation.

Curcumin – Curcumin is found in turmeric. Turmeric blocks a pro-inflammatory molecule, Nuclear Factor-kappaB (NF-kB) that turns on genes related to inflammation.

Antioxidants – Many berries like strawberries, blackberries, raspberries, blueberries and other cherries contain antioxidant compounds that have been shown to help reduce inflammation and help recovery from hard exercise.

Beetroot juice – Beetroot contain a micronutrient called betaine which has anti-inflammatory properties. It also dilates blood vessels to helps get plenty of oxygen to muscles when you exercise.

Cooked and sun-dried tomatoes – These are high in lycopene which activates antioxidant production in our cells, and is particularly beneficial for prostate health.

Onions, leeks and garlic – These are high in quercetin which turn off a pro-inflammatory gene called Tumor Necrosis Factor-alpha (TNF-a).

Cruciferous vegetables – These are broccoli, cauliflower, kale, Pac Choi, Brussel sprouts, cabbage, rocket, greens, horseradish, kohlrabi and Mizuna. If you cut up your cruciferous veggies an hour before cooking, it allows the formation of more sulforaphane which is a protective antioxidant and anti-cancer compound.

Herbs & Spices – These contain many natural compounds or “bioactives” which communicate to our cells. For example, turmeric contains Curcumin; garlic contains Allicin, ginger contains Gingerols, onions contain Quercetin, black pepper contains Piperidine, chilli’s contain Capsaicin. Many of these have been shown to have anti-tumor activity by stimulating tumor-suppressor genes.

Stress

Did you know that your response to stress is part-influenced by your genes? It certainly explains why some lucky individuals just seem to perform better under stress, whilst for others, high stress situations just makes them anxious and underperform under pressure.

Screenshot 2019-03-17 at 16.26.31

Chronic stress has been shown to shorten telomeres. Telomeres are the protective caps on the end of our chromosomes. An analogy would be like the protective plastic wrapping around the end of your shoe laces, preventing them from fraying. Each time a cell divides it loses a little bit of its telomere. This is repaired by an aptly-called enzyme, called telomerase. But long-term production of stress hormones like cortisol and adrenaline decreases available telomerase, so the chromosome’s lifespan is reduced. The cell dies prematurely and we age, just a little bit faster.

Part of our body’s stress response is controlled by the COMT gene, which regulates the body’s metabolism and detoxification of our chemical neurotransmitters, like dopamine.  Some of us have COMT genes that clear the brain of dopamine rapidly, allowing them to cope with stress and perform well under pressure.  These types have been nicknamed the “warrior-types”. While others have a slower and more steady response – the “worrier-type”. For these people, dopamine can build up in the brain’s frontal lobe.  This excess may cause the classic stress symptoms of anxiety, worry, panic attacks and insomnia. In severe cases it is thought to be associated with mental health problems including obsessive-compulsive disorder and schizophrenia.

This can seem depressing if genetic testing shows that you have a slow COMT gene variation. But the good news is that you can alter the impact that a slow COMT gene variation has on your body. Recent research suggests that those with slow COMT gene SNPs, although prone to worry, performed significantly better than those with fast gene SNPs in cognitive and memory tests, provided they were relaxed.  So, by learning to handle stress better, exercise regularly, and learn to reflect positively on your past successes, you can train yourself to see potential stressful situations as positive challenges and over-ride your natural predispositions.

In my last post, I will give you details of the DNAfit test. You can see exactly what you get for your money and decide if this genetic test is for you.

Part 4 – Weight management genes

Genetic variations (SNPs) are one reason why we have different appetites; are satiated by different amounts of food and have different food preferences. Our genes also regulate how insulin works in our body; how many fat cells we make and how full they can get. Our genes determine how well we can breakdown those stored fats and use them for energy. Our individual genetic profile influences what we can and can’t digest, our tendency to gain weight, absorb important nutrients and cope with toxins.

Let’s take a deeper look into the world of nutrigenomics and weight management.

The first thing to say is that nutrigenomics is a tool in the ‘diet toolbox’ that can help you manage your weight. It’s not the whole answer, of course not, but there are some valuable insights. Let’s start with how best to balance your carbohydrates, fats and proteins.

Macronutrient Balance

You can’t have failed to hear about how different macronutrient (protein, fat and carbohydrate) proportions influence our weight. Back in the 80’s we were told to eat a “low fat” diet, more recently, “high protein” was all the rage for fat loss, then “low carb” and “ketogenic”. Why is that? Why does one weight loss study conclude that low fat diets are the best for weight loss, while another study concludes that high protein diet are better? One reason is our genetic differences. Our SNPs make us respond differently to different macronutrients, particularly carbohydrates and saturated fats, and your genetic report will tell you which is best for you.

Low carbohydrate diets

Some of us are genetically predisposed to release more insulin when we eat carbohydrates. The carbohydrates make us hungrier and more likely to store excess calories as body fat. So, eating a diet with about 40% of our daily calories from carbohydrates, will lower insulin and reduce fat storage and weight gain. Balanced with more protein and fat, this diet is will be naturally more satisfying, so that the overall calories consumed are naturally reduced.

Low fat diets

People who have a high sensitivity to saturated fats lose weight on a low-saturated-fat diet. Minimising animal fats such as red meat, poultry skin, full fat dairy, eggs, cream, butter and lard will help them lose weight. Much better to eat good fats like avocado’s, olives, nuts, seeds, oily fish, olive oil. It goes without saying that avoiding hydrogenated fats found in margarine, baked goods, pastries, chips, crisps, as well as heating oils to very high temperatures are strictly off the menu for weight loss and health.

The Mediterranean diet

images

 

 

 

 

 

 

 

This diet has stood the test of time and is still one of the healthiest diets you can follow. It has been shown help people weigh less and also have lower risks for heart disease, depression, and dementia. A study was started in 1967 which recruited 120,000 nurses. The results were published in the BMJ in 2014. Those nurses who followed the traditional Mediterranean diet (lots of vegetables, fruit, nuts & seeds, pulses, fish, lean meat, olives & olive oil) most closely, had the longest telomeres.  What’s a telomere, I hear you ask? A telomere is a structure that covers the end of your chromosomes and protects your DNA from wear and tear. Telomeres naturally shorten with age, by measurable amounts. So, this study (among many of others) supports the benefits of the Mediterranean diet for longevity.

The Thrifty Gene

The ADRB2 gene has been called ‘the thrifty gene’. It’s one of a group of genes (PPARG TCF7L2, FABP2 and others) that conferred an advantage back in early human existence. It predisposes a reduced ability to release fat from storage, enabling the person to endure a typical feast-or-famine existence. This group of SNPs makes us sensitive to both saturated fats and carbohydrates. This means that as soon as your body senses fewer calories are being eaten (for example, on a diet) these genes then turn up your hunger sensations and turn on your cravings for higher calorie foods. In today’s hyper-caloric society, where there is always “feast” and no “famine”, those people with these SNPs are more likely to store body fat and become overweight. Reduction of total fat and refined carbohydrates (those that are quickly absorbed) is recommended for better weight management if you have these gene variations.

The FTO gene

One of the most studied genes is the FTO gene. It appears to regulate the amount of food we want to eat, and it impacts how well we tolerate fats, especially saturated fats. Particular SNPs on the FTO gene are also associated with obesity. But we can modify the expression of this gene. The Amish population have a high incidence of the obesity-predisposing FTO gene SNPs. However, they are not an overweight population because they work manually and are very active, keeping the genes switched off. Likewise, the same was found with elite athletes, none of whom were overweight, despite some of them having the FTO SNPs. So again, it seems that high exercise levels mitigate the risk of obesity. These are nice examples of how we can influence our gene expression, using exercise, in a positive way.

If you knew you had these SNPs that predisposed obesity, would you want to work harder to mitigate them? Would you exercise more and reduce saturated fat and refined carbohydrates in your diet? I think you would. Here’s one reason why. It has been shown in studies that eating a plant-based diet (I’m not saying vegetarian), eliminating processed fats and reducing saturated fats, combined with reasonable daily exercise down-regulates the FTO gene by 30%. Research seems to show that those people who follow diets that are genetically matched to their predispositions lose more weight and keep it off.

Please note that I have singled out some individual gene variations to discuss them. But it’s really important to realise that they don’t work in isolation. Our predispositions are controlled by clusters of genes working together, not just one gene working alone. That’s why your genetic report (the results you get if you take a test) list groups of genes, their variations, and the sum total effect of how they might all work together for you.

Fasting

Fasting is a way to modify your gene function or expression. Fasting turns on so-called ‘repair’ genes through a genetic process known as autophagy. This is a clever genetic process of ‘auto-self-destruct’ that cells go through when they have reached the end of their working life or become damaged. The cell breaks itself down and recycles the cell component parts. When you fast, human growth hormone goes up and insulin goes down. This helps you gain muscle and burn-off stored fat. Perhaps you may like to look into intermittent fasting for weight loss or weight management – there’s a wealth of positive findings supporting it.

Exercise

If I had to make one point about exercise, for weight loss, it’s this, “you can’t out-exercise a bad diet”. So, first things first: follow your genetically matched diet, then, exercise according to your power versus endurance profile (and be mindful of your injury risk and recovery needs).

Better still, take your test results to a personal trainer and let them work out the best way for you to achieve your weight-loss goals. Make your goals S.M.A.R.T (Specific. Measurable/Motivational. Actionable. Realistic. Time-based). Take small steps every day in the right direction and you will get there.

To summarise, our genes can increase or reduce our risk of developing diabetes and obesity but they don’t directly cause it. Rather, the diet we choose to eat and the activity levels we engage in each day, play the most crucial role.

In the next post, we will look at three crucial factors around genetics and ageing, DNA health, inflammation and stress.

Part 3 – My Story

Studying nutrigenomics, having my genes tested and having some blood tests done has given me two tangeable benefits. Firstly, I make food and exercise choices based on my genetic predispositions and nutrient levels.  And secondly, I relax about this being different to other people’s food and exercise choices. One-size-does-not-fit-all.

KONICA MINOLTA DIGITAL CAMERA

Vitamin D

You may know that I lived in the Middle East for three years. During that time, I studied Nutritional Therapy. As part of that learning, I took a vitamin D test and was shocked to discover that my vitamin D level was only 19 nmol/L. A good level is 50-60 nmol/L. How could that be when I was exposed to so much sunshine? Well, I only found out when I returned to the UK and later took a DNA test. I have the genetic variation (SNP) that reduces the production of an enzyme in the liver & kidneys that normally converts inactive vitamin D in the skin into the active form of vitamin D needed to make steroid hormones. I had a vitamin D deficiency because of my SNP. I now take a vitamin D supplement and measure my vitamin D levels each year to make sure they are in the healthy range. Now I feel more reassured that I’ve reduced my risk of developing osteoporosis; helped my immune system fight infections; reduced by chances of being depressed and having high blood pressure and I hope, my rate of cell ageing.

Caffeine

In the past, I had a condition called atrial fibrillation (AF). This is a condition when your heart beat goes very fast and irregular (in my case due to chronic stress, no down-time and years of lack of sleep). Occasionally, I can still feel my heart beat becoming irregular. Post treatment, I now manage it with lifestyle choices. I work hard to get eight hours sleep a night; I don’t do high intensity exercise every day and I meditate when I feel I need to (I should do it daily!). But I have also stopped drinking caffeine. I have learnt through genetic testing that I am a “slow metaboliser” of caffeine. I have a variation of the CYP1A2 gene that controls how quickly I break down caffeine. This means that, for me, too much caffeine can increase my risk of a raised heart rate, high blood pressure and heart attacks. So now I avoid it, or only have one cup, very occasionally. It also means that I don’t benefit from the physical/athletic performance enhancing effect of caffeine. By contrast, other people may have the “fast metaboliser” SNP. For them, this means they break down caffeine more rapidly, while preserving the healthy antioxidants in the coffee, which in turn may give them heart protection and give them athletic enhancing benefits too.

Salt

I reduce my intake of salt to less than one teaspoon per day because I have the ACE gene variation that predisposes me to high blood pressure if I eat too much salt. I measure my blood pressure at home and it’s mostly around 110/70. I eat a high plant-based diet, exercise regularly and try to manage my stress with meditation and yoga.

Wheat

On the whole, I avoid wheat and other gluten-containing foods because I have a SNP which increases my risk of developing coeliac disease. I have the HLA DQ2/8 genes, which increases my risk to 1 in 35, while the average is 1 in 100. Avoiding gluten is my choice, I don’t have to. But I know that anybody with this genetic predisposition can develop coeliac disease at any point in their life, so I just feel better knowing that I have lowered my risk. Let me be clear, this genetic test is not a test for coeliac. Only your doctor can diagnose coeliac disease with a blood test and a small bowel biopsy. Genes aside, if you want to know more about the effects of gluten on your health, your could Google Dr Alessio Fasano who is a paediatric gastroenterologist and medical researcher.

Exercise

MyDNAFit logoI’ve always been the “muscly-type”, one of those people who naturally puts on muscle easily, probably a mesomorph. I always thought it was because of my competitive swimming during secondary school. But perhaps this intense exercise wasn’t the whole story. I’ve now learnt that I have a high power to endurance profile. I’m 60% power versus 40% endurance. This may explain why I always swam the 100m freestyle and competed in short-course triathlons, not the not the 800m freestyle or endurance ironman! I get better fitness results from weight training and high intensity interval training compared to long endurance training. That isn’t to say the endurance training isn’t for me, just that I should keep endurance activities to about 40% of my training time, if I want to optimise my fitness.

Coupled with this, I have a fast recovery rate, meaning that I can do similar training on consecutive days without being too fatigued or getting DOMS. For other people who have a slower recovery rate, they would need to take more care to cross train different muscle groups, to optimise their training and recovery time. I have genes that predispose me to a high risk of ligament injury. Knowing this, I am mindful to make sure that I do my yoga and get massages if my joints ache. Cold water immersion is another anti-injury prevention technique you can use.

Using myself as an example in this post, you can see that I have learned some really useful things about my own genetic make-up since. Of course, I have always been into healthy living, so I was already doing many of the right things – I don’t smoke or drink, I eat a very healthy diet and I regularly exercise. But beyond these fairly well-established, common-sense ideals, I have learned to tailor how I eat and train to maximise my benefits. I’m over 50 now, so anything I can do to help my metabolism stay on top form and resist the natural propensity to gain weight, lose muscle mass, bone mass and injure myself, is a big help.

In the next blog we will look at how understanding your genetic variations can help you achieve your ideal weight.

Part 2 – Nutrients and genes

There’s a buzz-phrase used when learning about genes and nutrition,

“Genes load the gun, but environment pulls the trigger”.

What this means is that we may be predisposed to health challenges because of our gene variations (SNPs), but it’s what we do to ourselves that actually triggers a problem, or not. This is an important to remember. If we want to, we can always positively influence our health outcomes.

Environmental factors like exercise, stress, sleep, diet and pollution affect how our genes function. Cigarette smoke damages cellular DNA and causes mutations. Exercise has a positive effect on our health by optimising insulin and glucose levels. Some of the latest research into high intensity interval training is finding that this type of exercise triggers a release of anti-inflammatory chemicals from protein-encoding genes.

So, what about diet and gene interactions? There are two sides to this.

  • Our genes affect how we respond to food (nutrigenetics)
  • Food affects how our genes function (nutrigenomics)

nutrigenomics

 

Let’s work through a few examples of each.

Nutrigenetics (how genetic differences affect nutrients)

I am sure you know what micronutrient RDA’s are. They are the Recommended Daily Allowances for vitamins and minerals found in foods. You see them represented as percentages on food labels. It might say, “contains 30% of your RDA for iron”. These nutrient levels were calculated on what the acceptable level should be for an “average person” in “average health”. They give us general guidance. But these calculations are in no way matched to your genetic variations or to the levels of nutrients you currently have.

For example, 1 in 200 people in the UK and Ireland have a gene variation (a SNP) that predisposes them to absorb too much iron from their food. This means that over many years excess iron builds up in their body (it can’t be excreted). Men with this SNP who eat foods high in iron such as meat, liver, pate, shellfish, beans, lentils and spinach, risk liver, heart and pancreatic damage from the damaging effects of iron overload (Hemochromatosis). Women are less at risk because they lose iron through menstruation.

Here is another example. If you know what gene variation (SNP) you have on the BCO1 gene (Beta-Carotene Oxygenase gene 1), it will help you work out how much vitamin A you need to consume in your diet to keep your vision good, your immune system working well and your skin and mucus membranes healthy. Some people have a SNP on the BCO1 gene that reduces the production of the Beta-Carotene Oxygenase enzyme. This enzyme converts inactive beta-carotene (found in dark green leafy vegetables and orange coloured fruits and vegetables) into active Vitamin A for use in the body. If you know that you have that particular SNP on your BCO1 gene, then you might sensibly choose more animal foods over plant foods because they already contain active Vitamin A, while plant foods only contain inactive beta-carotene.

 

Nutrigenomics (how nutrients affect your genes)

Food metaphorically ‘speaks’ to our genes. Here’s a great health tip from the Institute of Functional Medicine, “brighter coloured whole foods, have the best language skills”. What it means is that if you eat a plate of rainbow-coloured fruits and vegetables every day, you are sending your genes all the right health messages.

You may be wondering how nutrients and food compounds influence this small but important proportion of protein-encoding genes? Well, they don’t actually change the order of the base nucleotides [Please read previous post], rather, they change the gene’s activity. They can activate it to make a protein, or they can de-activate it to stop making a protein. This is called gene “expression”. You may have heard such talk, of when a gene is “expressed” or not. It might be helpful to think of it this way. When a gene is in an active state, it is ‘expressed’, and then when a gene is ‘sleeping’, or inactive, it is ‘not expressing’.

A beneficial example is a compound in broccoli and other cruciferous vegetables (Brussel sprouts, cabbage, kale, cauliflower, Pak Choi) called sulphoraphane. Sulphoraphane can activate a gene which helps the body to detoxify harmful chemicals. Burnt or chargrilled meat, for example, contain harmful compounds called heterocyclic amines (HCAs) which can predispose us to colon cancer. So, it’s a smart move to eat your broccoli sprouts, cauliflower rice and coleslaw with your summer BBQ’s!

Plants make compounds, called phytochemicals, that protect them from attack. When we consume these phytochemicals, they help to protect us too. They help prevent DNA damage and they regulate inflammation. Some well researched phytochemicals are carotenoids, curcuminoids and flavonoids. You’ll find phytochemicals in brightly coloured fruits, vegetables, herbs and spices. For example, lycopene in tomatoes; lutein in leafy greens; beta-carotene in orange fruits and vegetables. Curcuminoids are found in turmeric root and flavonoids in green tea. So please, make your plate as colourful as you can and don’t underestimate the importance of these compounds for your genetic health.

The B group of vitamins are important for cell growth, energy production and DNA repair. Folate, or B9, is an important B vitamin which influences gene expression. The Latin name for Folate is “folium”, which means “leaf” and dark green leafy vegetables are high in folate. You may also know it as folic acid. Now, the MTHFR gene produces an enzyme responsible for converting inactive folate into active folate (I’ll spare you the technical names!). Once converted, the active folate is critical for making and repairing DNA and also for a multistep process that converts the amino acid homocysteine into methionine. Some people have SNPs on the MTHFR gene which slows folate enzyme activity, which when combined with low folate levels, can cause high levels of homocysteine. (MTHFR SNPs + low folate = high homocysteine). You don’t want too much homocysteine in your body because it has been associated with cardiovascular disease. People with the MTHFR SNPs would be well advised to test for their levels of folate and homocysteine. If needed, they can increase their intake of active methyl-folate from a supplement (not the commonly available synthetic folic acid).

When we know our nutrition-related SNPs and when we test our nutrient levels as well, we are in a good position to optimise our gene function and our long-term health. Thankfully testing our nutrient levels is now much easier and affordable. Although we can’t yet test for the level of every nutrient using a finger-prick blood sample, (compared to a full blood sample taken from a vein in your arm), we can take the following at-home test which we then send off in the post, for the following nutrients:

  • B12
  • Folate (B9)
  • Vitamin D
  • Zinc
  • Omega 3 & 6 fats
  • Iron

Please get in contact if you want to have any of these tests done.

In the next blog we will look at some of my own personal SNPs. I will share with you what I’ve learnt using some interesting examples of how I have used this knowledge in practical ways to optimise my health.

Part 1 – Introduction to genes

Up until recently, I thought that the genes I inherited from my parents told my body how to develop into the person I am. You know, brown eyes, 5′ 6’’, reasonable IQ! But I’ve never stopped to think that the way I have chosen to live my life, are actual instructions to my genes, telling them what to do, or what not to do. I never thought that I had some control over my gene function.

But our lifestyle and environment do play a significant role in shaping the way our genes work.  In this 5-part blog I want to explore how food and genes interact together and how can we design a lifestyle strategy to help us become more resilient to the effects of ageing.

You will have heard of the Human Genome Project, completed in 2003. It was the mapping of the entire code of 20,000 human genes, of which approximately 1.5% control the making of proteins (these are known as protein-coding or protein-encoding genes). We are going to look at a tiny fraction of those protein-encoding genes and how they interact with our diet to make us each individually unique.

A gene is just a segment of DNA that contains instructions for how and when your cell needs to make proteins. Enzymes are a good example of proteins. Enzymes control many of the body’s processes, particularly digestion. For example “lactase” is an enzyme responsible for breaking down the milk sugar, lactose. The LCT gene part-controls the production of the lactase enzyme from the lining cells of our intestine. For many humans, our ability to make the lactase enzyme naturally decreases with age.  As a result, people gradually lose their ability to digest lactose in later life, resulting in “lactose intolerance”. However, some people, particularly those from dairying populations, have developed “lactase persistence”. This means that their lactase-producing genes continue to make lactase and they can enjoy dairy products without digestive upset into adulthood.

Let’s now look at this diagram to help us understand some basic terminology.

Chromosome

The nucleus in the cell contains the X-shaped chromosomes, that you are probably familiar with. Humans have 23 pairs of chromosomes. When you unravel a chromosome, you can see that it is made of smaller and smaller parts that make up the double-helix of DNA. The smallest parts are the coloured blocks that make up the “rungs of the ladder” or in technical terms, the base nucleotide pairs. We only have four base nucleotides, Cytosine, Guanine, Adenine and Thymine. They are represented by the letters C, G, A and T.

The order of these nucleotides is very important. The order is the “recipe”, or set of instructions, for making a specific amino acid which are the individual building blocks of proteins. Different combinations of amino acids will make different proteins. And different proteins have different functions.

Now, the part of the story which explains how we are all different from each other. Humans are 99.5% identical to each other. The tiny 0.5% genetic variation is what makes us different from each other. Part of this variation is due to single changes in the order of the nucleotides. These very common changes are called Single Nucleotide Polymorphisms or SNPs (pronounced “snips”). We each have as many as 5-10 million SNPs. Please don’t be confused with a genetic mutation. Although SNPs and mutations are both changes in the base nucleotides, they are different. SNPs are much more common than mutations. Also, mutations can (but don’t always) impair the function of the genes, like in cystic fibrosis or sickle cell anaemia.

Coming back to SNPs. Many SNPs have no effect on health, while others are potentially very important. They may confer an advantage, like in the lactase example. A person with “lactase persistence” will have a different combination of base nucleotides, which tell the lactase-producing gene to keep making lactase. SNPs can also affect our risk for diseases like diabetes and heart disease; how we respond (positively or negatively) to pharmaceutical and recreational drugs; how effectively we break-down certain chemicals in our environment, that might include alcohol or caffeine; how we respond to the food we eat, including how easily we seem to put on body fat, or not, when we eat certain foods; and how we are affected, or not, by bacteria and viruses. Our individual SNPs can play a role in all these functions and more.

In the next post, we’ll focus on some SNPs that affect how our body responds to our food and also how the food we eat affects our protein-encoding genes.