The simple quiz that will reveal if YOUR organs are ageing too fast… and the lifestyle changes to turn BACK the clock

Are you waking up tired no matter how much you sleep? Does your brain feel foggy, your gut unsettled and your body bloated and miserable, whatever you try? You may have had blood tests to find the cause, only for them to come back as ‘normal’. Yet deep down, you know something isn’t right.

Millions of men and women silently struggle with chronic symptoms that don’t show up on blood tests or respond to standard treatments because the real problem is not being addressed.

Many doctors and medications only treat the symptoms of a condition – not the root cause, which lies deep in the 37 trillion cells of your body that work round the clock to keep you alive, energised and healthy.

When these cells are nourished, protected and activated, your organs stay young, strong and disease-resistant.

But when they become damaged – due to toxins and nutrient deficiency – the cells’ ‘powerhouse’ mitochondria are less able to produce and use energy. Cell membranes weaken, inflammation increases and chronic illness can take root.

What is tragic isn’t that our bodies wear down, but that most people don’t realise they can be rebuilt, so settle for managing symptoms rather than restoring health and vitality.

Yet your body is designed to regenerate: every day it replaces 330 billion worn-out cells with new ones.

Healing can happen surprisingly quickly. The lining of your gut can regenerate in just three to five days, while minor muscle injuries can take two to four weeks and minor bone fractures six to eight weeks.

Your liver – one of the body’s most powerful organs – begins to repair itself within just a few days of removing the source of the damage, such as alcohol or other toxins. Partial regrowth of healthy tissue takes around six to eight weeks, and complete regrowth roughly five months.

For someone with a fatty liver, this may mean regeneration begins in as little as two or three weeks after making healthy lifestyle changes.

We are both US functional medicine doctors with decades of clinical experience between us and specialise in treating the root causes of chronic disease. We regularly witness the body’s extraordinary regenerative capabilities in our patients.

Not so long ago, it was generally assumed that each generation would live longer than the last. In fact, a 2021 study in the journal Nature Communications estimated a human lifespan might even stretch to 120 or 150 years, so long as the systems regulating internal balance – i.e. the health of our cells – remained intact.

But now, instead, life expectancy is plateauing or declining in many parts of the Western world.

A recent large-scale study from Boston University found that Americans aged between 25 and 44 are dying younger than expected, with excess deaths – the number above what is normally expected – rising sharply in recent years, due to a cascade of lifestyle-driven diseases.

That’s because age isn’t just the number of candles on your birthday cake, it’s also a measure of how well your cells are functioning beneath the surface. And many people’s biological clocks are ticking much faster than they should.

One example is early menstruation. A little over a century ago, the average age for a girl’s first period was 17, but today it’s 12. One 2024 study by researchers from Harvard T.H. Chan School of Public Health found that the number of girls who began menstruating before the age of 11 had nearly doubled and the percentage menstruating before the age of nine more than doubled.

This isn’t simply early development, it’s premature hormonal ageing. The female body wasn’t designed to mature this quickly: a girl who begins menstruating at eight instead of 16 has a hormonal system that is ageing at twice the rate it should. This matters because earlier periods are linked with a significantly higher risk of breast cancer and type 2 diabetes.

More menstrual cycles over a lifetime means greater exposure to oestrogen, which stimulates breast tissue. Rising childhood obesity is thought to play a significant role, but exposure to hormone-disrupting chemicals, such as plastics and pesticides, processed foods and chronic stress could also contribute.

Meanwhile, testosterone levels in men have declined by over 30 per cent in recent decades, meaning a man in his 30s today may have the hormonal profile of a man in his 50s or 60s just a generation ago.

Fertility is dropping too. Sperm counts are reported to have fallen more than 50 per cent since the 1970s and women are seeing increased rates of polycystic ovarian syndrome (PCOS), irregular periods and early ovarian failure.

These aren’t just reproductive issues but signs of hormonal and systemic ageing at a cellular level.

One key culprit is a diet that’s increasingly dependent on ultra-processed foods (UPFs) – cereals, biscuits, ready meals, sliced bread and junk food – often high in hidden sugars.

Sugar disrupts the gut’s bacterial balance (as ‘bad’ bacteria feed on it), eventually leading to ‘leaky gut’ and body-wide inflammation. The liver also becomes overloaded trying to process excess fructose, common in packaged foods and fizzy drinks.

UPFs often contain industrial seed oils – including soybean, corn and sunflower – laden with omega-6 polyunsaturated fats, particularly linoleic acid, which may easily oxidise into unstable fatty acids.

It’s thought that these may impair the function of your cells’ mitochondria, responsible for turning food into energy in a usable form, known as adenosine triphosphate (ATP), the cells’ energy supply.

At the same time, modern diets are often deficient in key nutrients, particularly in omega 3 fatty acids, fibre-rich legumes, good quality protein, antioxidant-rich fruit and vegetables, olive oil and seeds and nuts.

Then there’s exposure to toxins from plastics and pesticides. A particular concern is man-made ‘forever chemicals’ known as PFAs, used in non-stick cooking equipment and food packaging, that don’t break down easily and build up in the environment.

These can cause changes in cells, particularly in the mechanisms controlling gene expression, potentially leading to an increased cancer risk.

A sedentary lifestyle is another fast track to premature ageing – and around a third of the global population is physically inactive.

A 2018 landmark study published in the medical journal JAMA Network Open found that being on the lowest rung of fitness is far more dangerous to your lifespan than smoking, high blood pressure or diabetes.

Research published in the journal Oncotarget in 2018 found that people who did high levels of exercise had longer telomeres – the protective caps on DNA that shorten with age – than those who are sedentary, suggesting that regular exercise might preserve the blueprint of your longevity at cellular level.

Chronic stress – whether due to a culture of overdrive or loneliness – is another problem, keeping cortisol levels raised and disrupting sleep and circadian rhythms, worsened by artificial and blue lights from laptops, mobiles and TVs. These affect the internal rhythm of your cells and their ability to heal.

Together, this toxic storm of modern life is wrecking the foundations of our health – depleting our cells of the energy they need to function properly, sending hormones spinning out of control, straining our metabolisms and locking our immune systems in non-stop fight mode.

But the good news is that there are simple practical measures you can take to transform your health, regardless of your age or genetics.

Not all organs age at the same rate. Just one ageing organ can quietly but significantly raise the risk of a serious health condition such as Alzheimer’s, a heart attack, diabetes or cancer.

We know this thanks to a groundbreaking 2023 study from Stanford University, involving nearly 5,700 participants, which found one in five adults over 50 has at least one organ ageing faster than the rest of their body – often with no outward symptoms.

The researchers used advanced technology and algorithms to analyse thousands of proteins in blood samples to estimate the biological age of 11 key organs, including the heart, liver, kidneys and brain, plus the immune system. They identified organ-specific proteins that act as biomarkers – a snapshot of how each organ functions beneath the surface.

A rapidly ageing heart, for instance, carried a 150 per cent higher risk of heart failure and an ‘older’ brain had an 80 per cent higher risk of cognitive decline. People with more than one ageing organ were over six times as likely to die early as those with none.

However, we now have the tools not only to identify which organ is ageing prematurely, but also to intervene and strengthen it at a cellular level – even before disease is diagnosed.

To test this, we conducted our own 12-week clinical trial, with 110 participants (90 women and 20 men) between the ages of 32 and 72.

They all followed a carefully structured longevity programme based on a whole-food, anti-inflammatory diet, supplements, daily stress-relieving techniques, sleep hygiene methods and regular movement. There were no crash diets or extreme measures.

Blood samples were taken at the start and end of the programme to measure biological age using a tested method tracking DNA changes and organ- specific biomarkers.

In just three months, cellular inflammation – the driver of most age-related disease – dropped dramatically and oxidative stress (the cellular damage caused by harmful chemical reactions in the body) also fell, showing that cells were repairing and neutralising damage more efficiently.

More remarkably, telomeres grew longer, representing an estimated one to three years of cellular youth regained.

Mitochondrial efficiency also improved, as did cardiovascular fitness as measured by VO2 max (how efficiently your body turns oxygen into energy).

Grip strength, an accepted measure of longevity that naturally weakens with age, improved, as did gut health, easing years of bloating, food intolerance and IBS symptoms for many.

What stood out most was that many participants saw radical improvements in several different types of symptoms – including type 2 diabetes, weight, PCOS, menstrual and menopausal symptoms, low testosterone and chronic fatigue – and not just one.

Others saw relief from long-standing digestive disorders, skin conditions such as eczema, migraines, anxiety, depression and chronic joint and nerve pain.

Now you can try the questionnaire for yourself.

Work out which part of your system is holding you back

Restoring your cellular health starts with identifying the organ or system holding you back. We’ve developed a simple questionnaire covering six major bodily systems, with practical action plans for each. We also suggest some easy tips to get you started – detailed plans are available in our new book, Heal Your Cells.

Today we will help you to assess the biological age of your immune system, hormones and liver. In tomorrow’s extract we will look at digestive and metabolic age, brain and mood age and heart age.

(Always consult your doctor or health practitioner before beginning any new diet, exercise or other regimen, particularly if you have a diagnosed condition or are taking medication.)

For each question, answer yes or no, based on the last 90 days. If unsure, answer no.

For each section, add five years for every ‘yes’ to an ageing factor. Subtract five for every ‘yes’ to a protective factor. Then add or subtract the total from your actual age.

Scores

-10 to 0 years: This organ is biologically younger than your chronological age. Keep doing what you are doing!

+5 to +10 years: Early signs of accelerated ageing. Start supporting this system now.

+15 to +20 years: Significant organ ageing. Make this system your top priority.

Immune Age

• Do you get sick more often than you used to, or recover slowly from colds or infections? (+5)
• Have you been diagnosed with autoimmune conditions or high inflammation (eg CRP, C-reactive protein)? (+5)
• Do you often feel burned out, stressed or emotionally weighed down? (+5)
• Do you experience frequent allergies, sinus issues or chronic congestion? (+5)
• Do you consistently sleep seven to nine hours a night? (-5)
• Do you spend time outdoors daily or engage in activities that bring calm and joy?(-5)

Immune age score in years

Your immune system is your body’s standing army – always on patrol for invaders such as disease, toxins and mutated cells. Every day, your body produces billions of new immune cells that circulate through the blood and lymphatic (drainage) system, with white blood cells stationed in bone marrow, spleen, lymph nodes, tonsils, thymus and gut. But with age, this army can falter and inflammation can take hold. The gut microbiome is key – containing around 70 per cent of all your body’s immune cells.

The immune system ages due to chronic low-grade, persistent inflammation, which damages tissues and accelerates disease risk and because the thymus, the gland that ‘trains’ disease-fighting T-cells, shrinks with age. An unbalanced, less diverse gut microbiome also disrupts gut-immune signalling and weakens the body’s defences.

But your immune system isn’t destined to weaken with age. Strengthening your gut microbiome with a nourishing whole food diet that’s full of antioxidant-rich vegetables, fruits and proteins, reducing stress with calming practices and increasing activity will help rebalance inflammation, reversing your biological immune age so you have fewer infections, recover faster and are better protected against chronic disease.

Try now

• Take vitamin D3 with your first meal. This regulates more than 200 immune-related genes, strengthening defences and preventing immune over-activation.

• Add garlic and ginger to one dish. Garlic is a natural antimicrobial and ginger has strong anti-inflammatory properties.

• Spend 20 minutes outdoors. Natural light can stimulate vitamin D production, balances circadian rhythm and lowers stress hormones. Fresh air and time in nature also improve microbe diversity and immune resilience.

• Bounce gently on a rebounder or small trampoline for five minutes. Regular exercise boosts circulation of the body’s defensive white blood cells, and rebounding on a mini trampoline is particularly effective – five to ten minutes stimulates lymphatic draining, circulation and detoxification.

Hormone Age

• Do you struggle with low libido, fertility issues, PMS/menopause symptoms or low testosterone? (+5)
• Do you feel exhausted in the morning or rely on caffeine to get through the day? (+5)
• Do you gain weight easily despite eating well and exercising? (+5)
• Do you have trouble handling stress, feel ‘wired and tired’ or notice frequent mood swings? (+5)
• Do you practise daily stress management (meditation, prayer, breathing exercises or gratitude)? (-5)
• Do you get at least seven hours of sleep per night and wake feeling rested? (-5)

Hormone age score in years

Hormones are the body’s chemical messengers, regulating energy, metabolism, fertility, mood, sleep and longevity. This system falters with age, stress, poor diet and toxin exposure, as the glands that produce hormones naturally weaken.

Toxin overload, environmental or dietary, can disrupt normal signalling. Chronic stress raises cortisol levels, interfering with normal sex hormone function, suppressing ovulation, lowering testosterone and accelerating menopause symptoms.

But with the right foods, therapies and lifestyle practices it is possible to improve your biological hormone age, restoring vitality and fertility.

A range of nutrient-rich foods and herbs can have a beneficial impact on hormone health in both sexes. These include grass-fed red meat, fatty fish, vegetables and seeds and nuts.

Try now

Men: Eat a serving of pumpkin seeds (1oz, shelled) – high in zinc, essential for testosterone production, sperm health and prostate function. Do 30 minutes of resistance exercise, two or three times a week. Strength training increases testosterone production and improves insulin sensitivity and bone density.

Women (fertility): Eat a handful of berries. Egg cells are particularly vulnerable to oxidative stress, which can affect their mitochondria and DNA. Berries are rich in antioxidants, particularly polyphenols, that help protect them. Drink a cup of cinnamon and ginger tea – both spices can help to regulate blood sugar and reduce inflammation.

Women (menopause): Take 1,000mg omega-3s to help reduce inflammation, protect the cardiovascular system, support brain function and improve joint mobility. Practise a stress-management technique – meditation or deep breathing – for ten to 20 minutes daily, shown to help reduce cortisol levels and ease menopausal symptoms.

Detox and liver age

• Do you regularly drink alcohol (3+ drinks a week) or take medications? (+5)
• Are you frequently exposed to harsh household cleaners, fragrances or chemical products? (+5)
• Do you struggle with resentment, anger or letting go emotionally? (+5)
• Do you sweat infrequently, rarely exercise or feel your body doesn’t ‘detox’ well? (+5)
• Do you drink the recommended six to eight glasses of water each day or do other detox supportive practices (e.g. sauna, dry-brushing)? (-5)
• Do you regularly eat cruciferous vegetables (e.g. broccoli, cauliflower, kale) or liver-supporting plants (such as matcha, dandelion)? (-5)

Detox/liver age score in years

Your liver, gallbladder and lymphatic system together form the body’s primary cleansing network – processing toxins, regulating hormones, balancing fats and keeping your body running smoothly. Your liver filters around two pints of blood a minute, detoxifying pesticides, alcohol, medications and metabolic waste.

The gallbladder stores bile, which helps break down fats and carries toxins out of the body. Meanwhile, the lymphatic system drains cellular waste.

With age, poor diet, an accumulation of toxins from plastics and pesticides and a sedentary lifestyle, these systems become overburdened – leading to a toxic build-up, liver fat accumulation and lymphatic congestion, which manifests itself as skin problems, fatigue, weight gain, hormone imbalance and even autoimmune flare-ups.

But by fuelling your body’s cleansing system with detoxifying foods, glutathione-supporting supplements (glutathione being a naturally occurring powerful antioxidant central to the liver’s detoxification pathways) and daily movement, you can reverse your ‘detox age’.

Try now

• Drink warm water with lemon or apple cider vinegar before your first meal. Lemons are high in vitamin C, which helps to ‘recharge’ spent glutathione into its active form and supports bile flow by thinning bile; and apple cider vinegar helps balance blood sugar and aids digestion and bile flow.
• Add steamed cruciferous vegetables to at least one meal. Broccoli, kale and cabbage contain sulforaphane and indole-3-carbinol, which boost detox enzymes and help clear excess oestrogen – a build-up can allow DNA-damaging by-products of oestrogen break down to circulate and reach tissues.
• Take 600mg NAC (N-Acetylcysteine) or liposomal glutathione. NAC boosts the raw material your liver needs to make glutathione, the molecule that binds to and neutralises toxins before flushing them out of the body. (We recommend a daily dose of 600-1,200 mg).
• Go for a brisk walk outdoors, for 20-30 minutes, two or three times a week. Exercise stimulates lymphatic drainage and circulation. Being outdoors also reduces cortisol levels.

© Josh Axe and Will Cole 2026

Adapted from Heal Your Cells, by Josh Axe and Will Cole (Transworld, £22). To order a copy for £19.80 (offer valid to 24/10/26; UK P&P free on orders over £25) go to mailshop.co.uk/books or call 020 3176 2937.