Camu camu, a small Amazonian berry exceptionally rich in vitamin C and antioxidants, has attracted interest as a potential natural remedy for non-alcoholic fatty liver disease (NAFLD). With NAFLD affecting approximately one in three UK adults and closely linked to obesity and metabolic syndrome, many people seek complementary approaches alongside conventional treatment. Whilst camu camu's impressive nutritional profile—including polyphenols and flavonoids—suggests theoretical benefits for reducing oxidative stress and inflammation in the liver, it is crucial to understand that no official link has been established between camu camu supplementation and improvement in fatty liver disease in humans. This article examines the current evidence, safe usage considerations, and NHS-recommended treatments for NAFLD.

What Is Camu Camu and How Might It Affect Fatty Liver Disease?

Camu camu (Myrciaria dubia) is a small, tart berry native to the Amazon rainforest, particularly found in Peru and Brazil. It has gained attention in recent years as a superfood due to its exceptionally high vitamin C content. Fresh camu camu fruit may contain approximately 2,000–3,000 mg of vitamin C per 100 g, though this varies widely depending on cultivar, processing, and storage. Processed powders and supplements often contain substantially less, so it is important to check product labels for actual vitamin C content per serving. By comparison, oranges and other citrus fruits contain far lower amounts. The berry is typically consumed as a powder, capsule, or juice concentrate rather than fresh, as its sour taste makes it less palatable in its natural form.

Non-alcoholic fatty liver disease (NAFLD)—also referred to in newer literature as metabolic dysfunction-associated steatotic liver disease (MASLD)—is a common condition characterised by excessive fat accumulation in the liver in people who drink little to no alcohol. It affects an estimated one in three adults in the UK and is closely associated with obesity, type 2 diabetes, and metabolic syndrome. The condition exists on a spectrum, ranging from simple steatosis (fat accumulation) to non-alcoholic steatohepatitis (NASH), which involves inflammation and can progress to cirrhosis.

The theoretical interest in camu camu for fatty liver disease stems from its rich antioxidant profile. Beyond vitamin C, the berry contains polyphenols, flavonoids, and ellagic acid—compounds that may help reduce oxidative stress and inflammation, both of which play key roles in NAFLD progression. However, the phytochemical composition of camu camu is variable and depends on growing conditions and processing. Oxidative stress occurs when there is an imbalance between free radicals and antioxidants in the body, potentially damaging liver cells and promoting fat accumulation.

It is important to note that whilst camu camu's nutritional composition is impressive, there is no official link established between camu camu supplementation and improvement in fatty liver disease in humans. Most evidence remains preliminary and based on laboratory or animal studies rather than robust clinical trials.

Evidence for Camu Camu in Non-Alcoholic Fatty Liver Disease

The scientific evidence supporting camu camu specifically for fatty liver disease is extremely limited. Most research has focused on the berry's general antioxidant and anti-inflammatory properties rather than liver-specific outcomes. A small number of animal studies have suggested potential metabolic benefits, but these findings cannot be directly extrapolated to human clinical practice.

One frequently cited study published in 2008 examined the effects of camu camu juice on metabolic markers in mice fed a high-fructose diet. The researchers observed improvements in markers of inflammation and oxidative stress, alongside reduced weight gain. However, this study did not specifically assess liver histology or established biomarkers of NAFLD such as alanine aminotransferase (ALT) or liver fat content measured by imaging.

Another area of interest is vitamin C's potential role in liver health. Some observational studies have suggested that higher dietary vitamin C intake may be associated with lower risk of NAFLD, though these associations do not prove causation. Vitamin C functions as an antioxidant and is involved in collagen synthesis, which could theoretically influence liver fibrosis. Nevertheless, supplementation studies using high-dose vitamin C alone have not demonstrated consistent benefits for NAFLD in human trials.

The polyphenol content of camu camu has also attracted research attention. Polyphenols may modulate lipid metabolism and reduce hepatic inflammation through various cellular pathways. However, the bioavailability of these compounds—how well they are absorbed and utilised by the body—remains uncertain, and as of 2024, there are no published human clinical trials specifically assessing camu camu supplementation in patients with diagnosed NAFLD.

Currently, there is insufficient evidence to recommend camu camu as a treatment for fatty liver disease. Patients should be aware that natural products are not automatically safe or effective. In the UK, food supplements are regulated as foods (with labelling and safety requirements) but are not licensed as medicines, so efficacy is not assessed before marketing and product content and quality can vary considerably.

How to Use Camu Camu Safely for Liver Health

If individuals choose to use camu camu as a dietary supplement, several practical considerations can help ensure safer use. Camu camu is most commonly available in the UK as a powder or capsule supplement, often marketed as a vitamin C source or general wellness product. These products are classified as food supplements rather than medicines and are not subject to the same rigorous testing and approval processes as pharmaceutical drugs.

Dosage considerations are important but challenging, as there is no established therapeutic dose for liver health. Most commercial products suggest 1–2 teaspoons (approximately 3–6 g) of powder daily or capsules providing equivalent amounts. However, it is essential to understand that these recommendations reflect manufacturer guidance and are not based on clinical evidence for NAFLD. The high vitamin C content means that excessive intake could potentially cause gastrointestinal upset, including diarrhoea, nausea, and abdominal cramps.

When selecting a product, look for reputable manufacturers who provide third-party testing certificates and clear labelling of ingredients. The powder should be stored in a cool, dry place away from direct sunlight to preserve its vitamin C content, which degrades with heat and light exposure. Camu camu powder can be mixed into smoothies, yoghurt, or water, though its tart flavour may require blending with other ingredients.

Certain groups should exercise particular caution or avoid camu camu supplements:

• Pregnant or breastfeeding women: There is insufficient safety data on high-dose camu camu supplementation during pregnancy or breastfeeding.

• People with chronic kidney disease: High vitamin C intake may increase the risk of oxalate accumulation.

• Those with a history of kidney stones: Particularly calcium oxalate stones, as vitamin C can be metabolised to oxalate.

It is essential to understand that camu camu should not replace evidence-based treatments for fatty liver disease. The cornerstone of NAFLD management remains lifestyle modification, including weight loss, dietary changes, and increased physical activity. Any supplement use should be discussed with a GP or hepatologist, particularly for individuals with confirmed liver disease, as professional monitoring of liver function is necessary.

Patients should inform their healthcare provider about all supplements they are taking, as this information is relevant for interpreting blood tests and assessing overall treatment plans. If you experience any adverse effects after starting camu camu, discontinue use and consult your GP promptly. Suspected side effects from any supplement can be reported via the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk).

Potential Risks and Interactions with Liver Medications

Whilst camu camu is generally considered safe when consumed in food-like amounts, several potential risks and drug interactions warrant consideration, particularly for individuals with liver disease or those taking medications.

High vitamin C intake is the primary concern. Camu camu's exceptionally high vitamin C content means that supplementation could easily exceed recommended levels. In the UK, the NHS advises that adults need approximately 40 mg of vitamin C daily. The Expert Group on Vitamins and Minerals (EVM) guidance suggests that taking up to 1,000 mg per day from supplements is unlikely to cause harm. Excessive vitamin C intake may cause:

• Gastrointestinal disturbances (diarrhoea, nausea, abdominal cramps)

• Increased risk of kidney stones, particularly calcium oxalate stones, in susceptible individuals

• Potential interference with certain blood glucose tests (see below)

• Pro-oxidant effects at very high doses, which could theoretically be counterproductive

For patients with existing liver disease, particularly those with haemochromatosis (iron overload disorder), high-dose vitamin C supplementation is potentially problematic. Vitamin C enhances iron absorption from the gut, which could exacerbate iron accumulation in the liver and worsen hepatic damage. Individuals with this condition should avoid camu camu supplements unless specifically advised by their hepatologist.

Drug interactions are another important consideration. Whilst specific interaction studies with camu camu are lacking, high-dose vitamin C may interact with several medications:

• Warfarin and anticoagulants: Evidence for a clinically significant interaction between vitamin C and warfarin is limited and inconsistent. However, patients taking warfarin should inform their anticoagulation clinic if starting high-dose vitamin C supplements, and INR (International Normalised Ratio) should be monitored as a precaution.

• Chemotherapy agents: There is theoretical concern that high-dose antioxidant supplements might interfere with certain cancer treatments. Patients undergoing chemotherapy should consult their oncology team before taking antioxidant supplements.

• Glucose monitoring devices: High levels of ascorbic acid (vitamin C) can interfere with some blood glucose meters and continuous glucose monitors (CGMs), potentially causing falsely low readings. Check your device manufacturer's instructions for specific guidance on ascorbic acid interference (for example, certain FreeStyle Libre models may be affected). If you use a glucose meter or CGM, discuss high-dose vitamin C supplementation with your diabetes care team.

Additional cautions:

• Chronic kidney disease: High vitamin C intake may increase the risk of oxalate accumulation and should be avoided or used only under medical supervision.

• History of calcium oxalate kidney stones: Vitamin C can be metabolised to oxalate; individuals with a history of stones should exercise caution.

Patients taking any regular medications should consult their GP or pharmacist before starting camu camu supplementation. This is particularly important for those with liver disease who may be taking multiple medications for associated conditions such as diabetes, hypertension, or dyslipidaemia.

NHS-Recommended Treatments for Fatty Liver Disease

The NHS and NICE provide clear, evidence-based guidance for managing non-alcoholic fatty liver disease (NICE guideline NG49), focusing primarily on lifestyle interventions rather than pharmacological treatments or supplements.

Weight loss is the most effective intervention for NAFLD. NICE guidelines recommend that overweight or obese patients with NAFLD should aim for gradual, sustained weight loss. Research demonstrates that losing 5–10% of body weight can significantly decrease liver fat content and improve liver enzyme levels. However, weight loss of 10% or more is most likely to resolve steatohepatitis (NASH) and improve fibrosis. Weight loss should be achieved through a combination of dietary modification and increased physical activity, typically aiming for 0.5–1 kg loss per week. Structured weight-management support and, where appropriate, obesity pharmacotherapy or bariatric surgery (according to NICE criteria) may be considered.

Dietary recommendations include:

• Reducing intake of refined carbohydrates, particularly sugar-sweetened beverages and foods high in fructose

• Limiting saturated fats and replacing them with unsaturated fats

• Increasing consumption of fruits, vegetables, whole grains, and lean proteins

• Following a Mediterranean-style diet, which has shown benefits in NAFLD

• Moderating portion sizes and total caloric intake

Physical activity is recommended at a level of at least 150 minutes of moderate-intensity aerobic exercise per week (in line with UK Chief Medical Officers' guidelines), such as brisk walking, cycling, or swimming. Resistance training should also be incorporated at least twice weekly. Exercise provides benefits even without significant weight loss by improving insulin sensitivity and reducing liver fat.

Alcohol advice: The UK Chief Medical Officers recommend that to keep health risks from alcohol low, it is safest not to drink more than 14 units per week on a regular basis. If you do drink as much as 14 units per week, it is best to spread this evenly over 3 or more days and avoid binge drinking. For people with NAFLD, minimising or avoiding alcohol altogether is advisable to reduce the risk of further liver damage.

Medical management focuses on treating associated conditions. This includes optimising control of type 2 diabetes, hypertension, and dyslipidaemia. Medications such as metformin, statins, and antihypertensives should be used according to standard guidelines for these conditions. Currently, there are no medications specifically licensed in the UK solely for treating NAFLD. Vitamin E and pioglitazone may be considered off-label in selected patients with biopsy-proven NASH under specialist supervision. NICE guidance suggests that vitamin E is generally considered for adults without diabetes, whilst pioglitazone may be used in adults with or without diabetes. The risks and benefits of these treatments should be discussed with a hepatologist.

Monitoring and referral are important aspects of care. Liver function tests (LFTs) alone are not sufficient for assessing NAFLD, as they may be normal even in the presence of significant liver disease. NICE recommends using non-invasive fibrosis scores in primary care, such as the FIB-4 or NAFLD Fibrosis Score (NFS), to assess the likelihood of advanced fibrosis. If these scores are indeterminate or suggest high risk, the Enhanced Liver Fibrosis (ELF) blood test should be arranged and/or the patient referred to hepatology services. Patients with evidence of advanced fibrosis or cirrhosis should be referred to specialist hepatology care. Patients should be advised to seek prompt medical attention if they develop symptoms such as jaundice, abdominal swelling, or unexplained weight loss, which could indicate disease progression.

Frequently Asked Questions