Can we use food as medicine?

“Let food be thy medicine and medicine be thy food,” Hippocrates supposedly once said. It’s a bold statement, especially now that we’ve moved into an era of modern medicine with an abundance of pharmaceutical drugs.  

Food will never replace medicines, but there’s no denying that our dietary choices can prevent, reduce symptoms of, or even reverse disease. In fact, a suboptimal diet may be responsible for up to one in five deaths worldwide — that’s more than tobacco [1]! 

Researchers are still looking into the effects of certain foods on long-term health. But what’s clear is there are some food groups which are undoubtedly protective against certain conditions. And these benefits are greatest when they’re regularly included as part of your diet, rather than a one-off detox. 

So, can we use food as medicine?

Can a healthy diet decrease your risk of disease? 

Some diets have been shown to be beneficial for certain conditions, either by preventing the condition or reducing the risk of complications, such as: 

1. Type 2 diabetes 
2. High blood pressure 
3. High cholesterol and heart disease 
4. Cancer 

1. Type 2 diabetes

Since the very nature of diabetes is to do with difficulty processing sugar, nutrition plays an extremely important part in the management of the condition.  

Making the right food choices can help you manage your blood sugar levels as well as reduce the risk of complications, like heart problems and strokes. If you’ve been told you have borderline diabetes (prediabetes), dietary changes can help to reverse the condition.  

Dietary tips for diabetes:  

• Choose healthier carbohydrates —Switch to more wholegrain foods, like brown rice, wholewheat pasta and couscous, whole oats, buckwheat, and quinoa. Many of these foods have the added benefit of a lower glycaemic index (GI), which means they’re broken down more slowly and avoid dramatic spikes in your blood sugar levels.  
• Cut down on excess sugar* — Common culprits include fizzy drinks, sweets, desserts, fruit juice, fruit syrups, smoothies, cakes, and biscuits. Try opting for healthier snacks if you can, like low-sugar yoghurts, unsalted nuts, and fruit (in moderation). Artificial sweeteners can be a safe alternative to added sugar — they can help to reduce calorie intake and reduce blood sugar spikes. However, be aware that some artificial sweeteners have been associated with digestive problems and disruption of the friendly bacteria in your gut [2,3]. There are also conflicting data on whether artificial sweeteners may contribute to weight gain due to an increase in appetite.  
• Reduce trans and saturated fats — Foods like biscuits, cakes, sausages, bacon, fried foods, cream, and cheeses are all high in ‘bad’ fats. With diabetes, your risk of heart disease is already increased. Eating these foods increases that risk even further by increasing cholesterol levels and causing weight gain. 

*If your diabetes treatment puts you at risk of hypos, you still may require sugary food or drink as part of your management plan.  

Can diabetes be cured or reversed with diet alone? 

A diabetes clinical trial (DiRECT) showed that half of type 2 diabetes patients were able to come off their medications after one year of participating in a weight loss programme that involved a low-calorie, nutrient-complete diet. Over a third of participants remained in remission even after two years [4]. 

This study proved that weight management through diet is critical for type 2 diabetes remission. 

Find out more about reversing prediabetes.  

2. High blood pressure

When it comes to high blood pressure, keeping your salt below recommended levels is key.  

The DASH eating plan, which stands for Dietary Approaches to Stop Hypertension, is proven to be just as effective as some of the first-choice treatments for high blood pressure [5].  

It’s a plant-focused diet — the combination of low salt, low-fat dairy products, and nutrient-rich vegetables make it not only effective at lowering blood pressure but also your risk of heart disease and diabetes.  

The fundamentals of the DASH meal plan are:  

• Limit salt intake — The DASH diet encourages no more than a teaspoon of salt a day. This refers to total salt intake rather than added salt. This can be a challenge and may require a few food swaps, as many snacks have a high sodium content. Watch out for salt in “healthier” foods like bread and cereals. 
• Choose fresh or frozen vegetables — Fresh vegetables tend to be best as they contain no hidden salt (unlike tinned vegetables). Good examples include broccoli, carrots, celery, cucumber, cabbage, peppers, and sweet potatoes. 
• Wholegrains — Wholegrains are types of grains where the bran and nutrient-rich germ are kept. It doesn’t have to be an ancient grain you’ve never heard of. You could try incorporating the following into your diet: Weetabix, bran flakes, popcorn, wholemeal bread, wholewheat crackers, brown or wild rice, oat cakes, or wholegrain cereal bars.  
• Fruit — Fruit is a much healthier way to fight sugar cravings than other types of dessert. Try pomegranate seeds on your salad, clementines, apples, bananas, raspberries, and pears.  
• Switch to low-fat dairy products — Choose dairy products that are low in fat, like 1% fat milk, cottage cheese, Manchego cheese, and low-fat Greek yoghurt.  
• Nuts, seeds, and beans — Nuts are often high in fat, so try to limit yourself to four or five servings a week. An example of a serving is about a third of a cup of almonds, walnuts, or peanuts. Legumes are also brimming with goodness, so stock up on chickpeas, black beans, lentils, and kidney beans.  

Drinking too much alcohol over time will also raise your blood pressure, and heavy drinking raises it further. So, cut back if you can, ideally to no more than 14 units per week.  

Most research agrees that garlic can help to reduce blood pressure [6,7]. However, most of these studies looked at garlic extracts, or powder, rather than cloves of garlic used in cooking. You shouldn’t rely on this ingredient alone to lower your blood pressure, but it’s an excellent nutrient-rich vegetable that can add flavour to your cooking without adding salt. 

Here’s how to keep an eye on your blood pressure at home.  

3. High cholesterol and heart disease

Because high blood pressure puts strain on the heart, a low-salt diet is vital for heart health. But just as important is your balance of good versus bad cholesterol. When bad cholesterol builds up in the arteries, it can cause a partial or complete blockage, leading to coronary artery disease and heart attacks.  

For high cholesterol specifically, Heart UK offers an Ultimate Cholesterol Lowering Plan. It incorporates four main groups of cholesterol-lowering foods, which are:  

• Soya foods — These include tofu, edamame beans, soy nuts, and soya meats.  
• Oats and barley — These wholemeal grains are rich in beta glucans which bind with cholesterol-rich bile acids and prevent them from being absorbed. 
• Nuts — Unsalted nuts with their skins are best. They’re packed with heart-healthy nutrients and rich in good fats. Stick to no more than a handful per day.   
• Sterols and stanols — These substances are similar to cholesterol but derived from plants. Some foods are fortified with sterols/stanols, like yoghurts, cereal bars, spreads, and milk. Don’t exceed more than 3g per day.  

These cholesterol-lowering foods on their own are unlikely to make a huge difference to your cholesterol. Just as important is trying to minimise your intake of saturated and trans fats. Swap butter, whole milk and fatty meats to skimmed milk, low-fat meats, and vegetable oil spreads. Avoid hydrogenated fats and oils often found in spreads — be sure to check the ingredients.  

When looking at heart health as a whole, one of the most accessible heart-friendly diets is the Mediterranean diet. A Mediterranean dish tends to be not only rich in flavours and colours, but nutritionally balanced too. It’s less restrictive than some other diets but has been researched extensively and shown to reduce your risk of heart disease [8].  

Tips on a heart-healthy diet:  

• More veg, less meat — Most heart-healthy diets are plant-focused. The reason for this is that many types of meat, especially red meats, are high in saturated fats. It’s best to switch to poultry, or better still, oily fish. Try to vary the types of fruit and vegetables you eat and aim for a minimum of five portions a day. A portion is about a handful. For example, four broccoli florets, a pear, three heaped tablespoons of carrots, or eight strawberries each count as one portion. 
• Switch to wholegrain — Wholegrain foods seem to appear in most scientifically proven diets and there’s a reason for this: they are high in nutrients and fibre, reduce inflammation, and reduce your risk of heart disease, stroke, obesity, and type 2 diabetes. 
• Limit your saturated fats — Foods high in saturated fats include fatty cuts of meat, fried foods, biscuits, and most desserts. Switch to healthier unsaturated fats like olive oil, cashew nuts, avocados, and oily fish if you can. There’s conflicting evidence around dietary fat recommendations [9]. Fats should be enjoyed in moderation like most food groups but are still high in calories.  
• Reduce your salt intake — The NHS recommends having no more than 6g of salt a day. This can be difficult as salt hides in some foods. Watch out for processed meats, smoked fish, ready meals, pretzels, crisps, stock cubes, canned vegetables, and sauces, like soy sauce. The NHS gives tips on reducing salt intake.    

Find out more about how you can eat to beat heart disease. 

4. Cancer

Eating a healthy and balanced diet can reduce your risk of cancer. This is partly due to the effect of the diet itself, but also by helping you maintain a healthy weight — obesity is a cause of at least 13 types of cancer [10]. 

Some foods can increase your risk of cancer (but eating these doesn’t mean you’ll definitely get cancer).  

Foods that may increase your risk of cancer include:  

• Processed and red meat — Both can increase your risk of bowel cancer. You can still enjoy these foods but in moderation. The NHS advises eating no more than an average of 70g per day [11]. If you can, substitute some of your meat dishes with oily fish or more plant-based dishes.   
• Alcohol — Alcohol-associated cancers include mouth, throat, voice box, oesophagus, liver, breast, and bowel [12]. Generally, the risk increases the more you drink. 
• Fatty foods — Fatty foods contribute to weight gain which increases your risk of many types of cancer. Saturated and trans fats are the most harmful.   

Some food groups are protective against cancer [13]: 

• Antioxidant-rich fruit and vegetables — Making sure you eat plenty of fruits and vegetables can be protective against bowel, breast, and lung cancer. And fruit, on its own, is protective against prostate cancer. 
• Fish (instead of red meat) — Fatty fish has been shown to lower the risk of both bowel and breast cancer.  
• Calcium and yoghurt — Greater calcium and yoghurt intake is associated with a lower risk of bowel and prostate cancer.  

Once again, the Mediterranean diet stands out as a protective diet against cancer, especially bowel and breast cancer [13].    

Many fruits and vegetables contain antioxidants and other anti-inflammatory compounds which can protect the body from damaging free radicals, many reducing the risk of cancer.  

Antioxidants and their sources: 

• Beta-carotene — Carrots, sweet potatoes, butternut squash, spinach, and kale. 
• Lycopene — Guavas, tomatoes, watermelon, red peppers, and grapefruit. 
• Resveratrol — Red grapes, blueberries, peanuts, and dark chocolate. 
• Selenium — Brazil nuts, fish, shellfish, tofu, wholewheat pasta, and mushrooms. 
• Vitamin C — Guavas, peppers, broccoli, strawberries, oranges, papaya, and kiwi. 
• Vitamin E — Sunflower seeds, almonds, avocados, spinach, and kiwi.  

Let food be thy preventative medicine 

The upshot is that yes, your diet can greatly affect your risk of certain diseases and, in some cases, reverse the effects of disease. A lot of it comes down to wholegrain foods, plenty of greens, and limiting your intake of harmful fats, processed foods, and artificial sugars.  

But diet alone isn’t a heal-all. We mustn’t forget the other factors that contribute to a healthy lifestyle, like exercise, sleep, and managing stress levels. These are just as important. 

Shop our Wellness Tests and see how you can optimise your health and identify your risk of some lifestyle-related diseases.

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References 

1. GBD 2017 Diet Collaborators. Health effects of dietary risks in 195 countries, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017. Lancet. 2019 May 11;393(10184):1958–72.
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10. Does eating a healthy diet reduce my risk of cancer? [Internet]. Cancer Research UK. 2019 [cited 2022 Jun 20]. Available from: https://www.cancerresearchuk.org/about-cancer/causes-of-cancer/diet-and-cancer/does-having-a-healthy-diet-reduce-my-risk-of-cancer
11. Red meat and bowel cancer risk [Internet]. nhs.uk. 2022 [cited 2022 Jun 20]. Available from: https://www.nhs.uk/live-well/eat-well/food-guidelines-and-food-labels/red-meat-and-the-risk-of-bowel-cancer/
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