our resources.
NUTRIGENETICS
If you happen to have a family history of heart disease, you may be thinking to yourself that your genes are your destiny and there isn’t much you can do about your ‘dirty DNA’. On the contrary: studies have shown that we are more in control of our heart disease risk than previously thought. Our genetic blueprint is inherited from our parents; this information is stored in every cell of your body and it is unchangeable. However, we can change the OUPUT of our genes by changing what we put IN to our system.48 The ability to change the expression of our genes is a concept I introduced in my first book. Nutrigenetics, nutrigenomics and epigenetics are among a few novel science disciplines that focus their attention on the role of nutrients and bioactive food compounds in gene expression.49 When I personally learnt more about this field, it revolutionised my perspective on just how important food and our lifestyle is.
Once we begin to understand and believe in the power of environmental influences on the very foundations of our existence, it becomes clear why diet is one of the most technologically advanced treatments we have in our armoury against disease. When you consume food it ‘speaks’ to your DNA and this communication can either lead to an overall positive or negative outcome. By introducing colourful foods, nutrient-dense ingredients and good-quality fats (which all the recipes in this book contain) we not only provide micronutrients and proteins for heart function, but we are also changing the messages transmitted via our DNA.50 Cardiologists are now warming to the idea that nutrigenomics has a role in their speciality and I see more specialists attending lectures in nutrition, engaging with me on social media and at talks, wanting to learn more. This area of research gives us further mechanistic information about why particular diets like the Mediterranean diet are so cardio protective50 and I’m sure biomedical informatics will help tackle the complexity of this field.
What we can be certain of is that the root cause of – and solution to – the clear majority of cardiovascular diseases that I see in the emergency department and primary care is manageable with lifestyle. This fact alone should give us a clue as to where we should be concentrating our attention and resources.
STOP THE STRESS
Beyond the nutrients necessary for contracting the muscular walls of our heart, this organ is vulnerable to ‘oxidative stress’, a topic we discuss in the chapter exploring inflammation (here). High levels of inflammation have been shown in many animal and human models to be detrimental to the walls of arteries.51 Oxidative stress can be created by high blood pressure, smoking, as well as high-sugar diets that can lead to the creation of ‘advanced glycaemic end products’ (AGEs). These products concentrate in parts of the heart vessels creating inflammation that can lead to plaque formation.52 By ensuring your lifestyle reduces inflammation, limits foods high in sugar and refined carbohydrates (like white rice, bread, pasta, cookies and cakes) you can prevent unnecessary oxidative stress and fuel your body’s natural inflammation-balancing mechanisms.
A Mediterranean-style diet has been shown to reduce oxidative stress, lower blood pressure and improve the health of blood vessels.41 In addition, a diet high in green vegetables such as broccoli, parsley and sprouts not only contains oxidant scavengers like vitamin C and heart-stabilising minerals like magnesium,53 but phytochemicals including sulfurophane, indole-3-carbinol and quercetin that are known to be potent anti-inflammatory ingredients.54
‘Whole sources of fat such as pecans, walnuts, sunflower seeds and minimally-processed extra-virgin olive oil are fantastic additions to your diet from a heart-health perspective.’
BALANCED FATS
Despite years of being told fat should be stripped out of our diets, sources of good-quality fat such as nuts, seeds and extra-virgin olive oil feature heavily in Mediterranean diets which are heart healthy. The detrimental low-fat message needs to be addressed. It’s been heavily over-simplified and it’s a confusing topic for many patients who still believe all sources of fat are harmful. To put it simply, whole sources of fat such as pecans, walnuts, sunflower seeds and minimally-processed extra-virgin olive oil are fantastic additions to your diet from a heart-health perspective. Not only do they contain key minerals like selenium and magnesium but they provide antioxidants such as vitamin E, which can protect the heart from oxidative stress.55 Algae oil and wild oily fish also contain long-chain Omega-3 fatty acids that have been shown to be anti-inflammatory56 and vital additions to a heart-healthy diet.
Two types of fatty acids, Omega-3 and Omega-6, have been given a lot more attention in studies trying to explain the rise of heart disease in western countries. Omega-6 is found in cereals, wheat and animal products but also within vegetable oils, nuts and seeds. Omega-6 is generally thought to be pro-inflammatory but, as we will learn in the inflammation chapter (here), the process of inflammation is essential for our body and this is why we need some sources of Omega-6 in our diet. The issue appears to arise where the ratio of Omega-6 to Omega-3 in our body falls out of balance. Throughout our evolution we would have had equal amounts of 3 and 6 or a ratio between 1:1 to 1:4.57 However, western diets high in poor-quality industrial corn and soy oils, refined cereals, wheat and animal products tip the balance to one that has a much higher ratio of Omega-6 than is sensible for human health.
The mechanism by which different fats impact our health is more complicated than simply turning inflammation on and off. Fatty acids modify the blood’s ability to clot and even influence gene expression of cells in our vessels.58 To put it simply, it’s all about ratio, but rather than suggesting we all diligently calculate our Omega-3 to Omega-6 percentages, my advice would be to concentrate your fat sources on whole foods such as nuts and seeds. Use minimally processed oils like extra-virgin olive oil and limit your intake of biscuits, fried foods and refined snacks like crisps. Follow these principles and your ratios are likely to be optimal for general as well as heart health without having to obsess about the numbers.
Our plates are a gateway to using the thousands of compounds that assist our body’s inherent ability to look after itself. Recipes such as my Aubergine and Walnut Ragu (see here) or the Jambalaya (see here) are great examples of the types of food we need to concentrate our diet around. These include vegetables, fruits, spices and specific fats that help reduce our risk of heart disease through a multitude of cellular processes. Here are some of the foods I regularly recommend in clinic to patients interested in heart-healthy meals:
+ A rainbow of colours There is a significant body of clinical data and large studies to demonstrate that antioxidant-rich diets reduce blood pressure and cardiovascular risk59 and, as a general rule of thumb, colours mean antioxidants. Look for a rainbow of colours in your diet and you’re likely to be including a plethora of micronutrients that will positively impact your heart. Of particular note, I like to include red and purple foods such as berries, beetroot, red cabbage and grapes. These contain phytochemicals such as the betalains and anthocyanins that have been shown to relax blood vessels and lower high blood pressure.60, 61, 62
+ Calcium and potassium These minerals are essential for vascular health. You’ll find calcium in ingredients such as chickpeas, puy lentils and sesame seeds, and both potassium and magnesium are abundant in dark greens such as cavolo nero, spring greens and Swiss chard. The heart is an energy-generating organ that relies on these minerals to appropriately conduct electricity through its tissue fibres. By eating these types of foods, you ensure the availability of these essential nutrients
