“One of the biggest misconceptions is that an anti-inflammatory diet excludes different food groups. It’s actually very inclusive,” says Dr Shilpa Ravella. Photo / Mariana Medvedeva, Unsplash
In the past few years, a new buzzword has entered conversations about illness and disease. Doctors are increasingly talking about “inflammation” – a term which describes the automatic response – or flaring up – of the body when it tries to fight infections, toxins and trauma.
Until recently, inflammation has generally been used to describe something you can see: the redness of a stubbed toe, or the “-itis” of a swollen pair of tonsils or appendix. Then there are the auto-immune conditions such as inflammatory bowel disease. But now attention is being given to “hidden” inflammation, a chronic, insidious lifelong process that could be responsible for common conditions from heart disease to cancer and Type 2 diabetes, and even depression and dementia.
Dr Shilpa Ravella is a transplant gastroenterologist, assistant professor of medicine at Columbia University Medical Centre and the author of a new book: A Silent Fire: The Story of Inflammation, Diet and Disease.
“We used to largely talk about inflammation as a consequence, not as a root cause, of a disease,” she says. “But in the past couple of decades, there is increasing evidence that inflammation itself can cause or is associated with higher rates of chronic illness. Inflammation affects ageing, the germs in our gut and the function of our intestines.”
In the short term, inflammation is a normal healthy response to invaders. When your body encounters an offending agent – such as viruses, bacteria or toxic chemicals – it activates the immune system. Your immune system sends out its first responders: inflammatory cells and cytokines (substances that stimulate more inflammatory cells) to neutralise the intruders or to start healing injured tissue. In acute inflammation, the body jumps to immediate attention – for example, healing a cut. But with chronic inflammation, your body continues sending inflammatory cells even when there is no outside danger.
We are used to seeing acute inflammation on a daily basis, for example when we hit our knee against a table and it reddens and heats. “This is a manifestation of inflammatory changes occurring on a microscopic level, owing to increased blood flow and the dilation of blood vessels,” says Ravella. “Scientists have long known that, while being of benefit to a host organism, inflammation can also cause tissue damage.” But hidden inflammation is not always visible to the naked eye. It happens deep in the body – in our gut, our pancreas, our blood vessels.
As we age, our immune response becomes less well regulated and chronic inflammation can persist for months or years, with the immune system engaging in prolonged “friendly fire”, damaging the body over time. Right now, patients walking into their GP’s office are unlikely to be routinely tested for hidden inflammation (although a cardiac clinic may test for an inflammatory marker called high-sensitivity C-reactive protein – or CRP – which is produced by the liver).
“But testing for inflammation ‘proxies’ can be telling,” says Ravella. “For example, fat around the belly – which is a marker for the highly inflammatory visceral fat that wraps around inner abdominal organs – or high blood sugars, are signs of hidden inflammation.”
Ravella is particularly concerned with what she terms the “skyrocketing” of conditions such as obesity, Type 2 diabetes, allergies and cancer – which she terms “inflammatory diseases”. Repeated studies over the past 20 years, including two in the influential New England Journal of Medicine, have shown a firm link between inflammation and cardiovascular disease, as chronic inflammation plays a role in atherosclerosis, or hardening of the arteries. Similarly, research suggests that chronic inflammation may play a part in DNA damage and gene alterations associated with several types of cancer.
“We now know that many of our chronic conditions are – at least in part – inflammatory disorders. By preventing or treating the inflammation, we may be able to decrease the risk of future disease,” says Ravella. “For example, half of people with heart disease do not have high blood cholesterol levels, which is a common risk factor for developing heart disease. But studies have shown that when we treat low-level inflammation, you can lower the risk of a future heart attack or stroke.”
Inflammatory diseases are the most common cause of sickness and death in the world today, says Ravella. “Genetics play a part in these conditions (in some more than others) but they can’t be the only cause. Research is increasingly showing that many inflammatory diseases are largely lifestyle disorders.”
Of course, we can’t change our genes, but we can change our lifestyle. Read on for simple anti-inflammatory lifestyle tweaks that could add years to your life.
Unsurprisingly, diet is key
“So much of the anti-inflammatory approach involves your diet, which in turn affects the gut microbiome – the helpful germs inside our intestines,” says Ravella. “Fibre is anti-inflammatory and vital for the health of your gut germs. Few of us get enough fibre.”
UK research backs up her assertion: according to a 2022 report from Action on Fibre, only 9 per cent of UK adults meet the recommended amount. In 2015, the government increased the dietary recommendation from 24g to 30g per day and since then there has been very little change in the UK population intake.
Much of Ravella’s book devotes itself to the benefits of the Mediterranean diet, which is based on high-fibre and anti-inflammatory plant-based foods, where the main source of fat is olive oil, and red meat and sweets are treats, eaten only occasionally.
Perhaps the biggest advert for the Mediterranean diet is the man who “discovered” and promoted it: physiologist Ancel Keys died in 2004, just shy of his 101st birthday.
Variety matters
“One of the biggest misconceptions is that an anti-inflammatory diet excludes different food groups. It’s actually very inclusive,” says Ravella.
According to Action on Fibre: “Over the years government policy has focused on reducing the amount of calories, salt and sugar we consume, but there has been little focus on increasing foods and nutrients we need more of.” Maybe it’s time to take note.
Ravella counsels patients to fill their plates with as diverse an array of plants as possible. “This includes foods we have been conditioned to avoid: wholegrains – even beans and those containing gluten – are anti-inflammatory foods,” she says. Cruciferous vegetables, such as broccoli, cauliflower and kale, are especially healthy because they contain molecules called isothiocynates, which remove toxins, prevent DNA damage, and kill cancer cells.
“They offer powerful protection against chronic inflammatory diseases,” says Ravella. She also recommends the soluble fibre found in bananas, oatmeal and beans. “Gut bacteria love these foods. They ferment soluble fibre to make short-chain fatty acids which lower inflammation in the intestines and throughout the body.”
Repeated research, including a 2019 study in Clinical Nutrition, has shown that foods high in polyphenols – colourful berries, citrus fruits, wholegrains and nuts – combat cancer-inducing free radicals and regulate inflammatory markers including CRP. Mushrooms are a natural source of vitamin D, known for helping the body absorb calcium and support the immune system. Onions and garlic also stimulate immunity and support gut bacteria.
Foods to avoid
“The immune system responds to the Western diet, loaded with modern animal fare, sugar, salt, refined carbohydrates and processed foods, as it would a noxious germ,” says Ravella. “Studies in both animals and humans show that this diet can directly activate the immune system, stressing cells in our body and prompting immune cells to produce an overload of inflammatory molecules, and fewer anti-inflammatory ones.”
So these are the foods to swerve: high-sugar breakfast cereals, crisps and other salty foods, processed meats including bacon and sausages, fizzy drinks, anything with corn syrup and excess saturated fats.
Do I really have to give up meat?
“Modern animal foods are not the same quality as those eaten by our ancestors,” says Ravella. “For example, antelope flesh, which anthropologists suggest is similar to Paleolithic meat, is leaner and higher in omega-3 fats than modern meat. Meanwhile, there is increasing evidence that animal protein is harmful for the body, leading to an excess of toxic substances such as hydrogen sulphide in the gut, which is tied to diseases like inflammatory bowel disease, and even cancer.
“People sometimes claim that a low-carb diet high in modern animal foods helps them to lose weight, but the inflammation created by these foods can be silent and insidious, so the cost of routinely consuming these foods is not always initially apparent.”
A poor diet can still lead to visceral fat and hidden inflammation, even in the absence of visible belly fat.
In the early 1970s, Ancel Keys – he of Mediterranean diet fame – observed a group of super-fit Finnish loggers who lived on a diet of red meat, butter and eggs, but were dropping dead of heart attacks at the highest known rate in the world.
Ravella’s message here is clear: cut back on the animal foods in your diet. In particular, minimise or avoid red and processed meats.
“If you choose to include animal foods in your diet, maximise your fibre intake first, and then choose high-quality fermented dairy, eggs, seafood and lean poultry in small proportions that align with traditional dietary patterns – like the Mediterranean diet.”
How we prepare our food matters
“Gentle cooking methods are best for our bodies and the germs within them,” says Ravella. So steaming, stewing and boiling is healthier than high-heat grilling, frying or roasting.
Intermittent fasting can help
Eating is, in itself, an inflammatory act. Ravella says: “Cutting down on our windows of consumption propels the body into clean-up mode.” While some intermittent fasting regimes become ever more challenging and tricky to achieve, Ravella suggests eating in an eight- to 10-hour window – for example, 8am to 6pm – as a form of fasting that is easy to achieve.
Even moderate exercise works wonders
“Research shows that regular, moderate exercise – like brisk walking, bicycling, jogging, and strength training – helps to prevent all kinds of chronic inflammatory diseases, while inactive lifestyles feed them,” says Ravella. “It melts away inflammatory abdominal fat, helping to ward off heart disease and strokes. Even in the absence of weight loss, exercise can modulate low-level inflammation.”
De-stress with friends – and rest
“Stressful situations alter the actions of immune cells and are tied to a rise in inflammatory blood markers,” says Ravella. “A lonely individual, for example, is more likely to become inflamed when beset by challenges at work than someone rich in social support.”
It’s easier said than done, but try to get enough sleep. Meditation and yoga can also bring anti-inflammatory calm.
Second-hand clothing can be a reservoir for many potentially dangerous microbes.