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Nonalcoholic Fatty Liver Disease

Fat accumulation in the liver unrelated to alcohol, now the most common chronic liver disease, affecting about 30% of adults worldwide1. Driven by insulin resistance, refined carbs and fructose. Liver fat responds well to weight loss and dietary change, and the earlier stages can improve substantially.

Liver, Gallbladder & Pancreas Evidence-Based

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Definition

What Is NAFLD?

Nonalcoholic Fatty Liver Disease (NAFLD), recently renamed MASLD (Metabolic dysfunction-Associated Steatotic Liver Disease), is excess fat accumulation in the liver (>5% by weight) that is not caused by significant alcohol consumption. It's now the most common chronic liver disease, affecting about 30% of adults worldwide1 and a majority of people with type 2 diabetes.

NAFLD is fundamentally a disease of metabolic dysfunction. Excess fructose, refined carbohydrates and chronic insulin resistance drive fat (triglycerides) into liver cells. Once accumulated, this fat triggers inflammation, oxidative stress and progressive liver damage. The condition is the hepatic manifestation of metabolic syndrome.

The encouraging news: NAFLD is among the more modifiable chronic conditions. With sustained weight loss, whatever the diet, liver fat falls, and many patients see substantial improvement with weight loss and dietary change alone23.

โš ๏ธ NAFLD progresses silently for years. Most people only ever have the first stage; a small number develop NASH (the inflammatory form)16, and some of them progress to cirrhosis. NASH was the second most common reason for liver transplants in the US in 2019, and the fastest rising27. Early changes can improve the liver substantially; once scarring is advanced, improvement is much harder.
A healthy liver above a pale yellow fatty liver and a figure with abdominal fat; icons show the risk factors type 2 diabetes, high cholesterol and excess weight

Stages of NAFLD Progression

Simple Steatosis (NAFL)

Fat accumulation without inflammation. Asymptomatic. Liver fat can fall within weeks to months of dietary change. The vast majority of cases stay here, and aggressive lifestyle change resolves it.

NASH (Nonalcoholic Steatohepatitis)

Fat + inflammation + hepatocyte damage. Affects a minority of people with NAFLD; most only ever have the first stage16. Elevated liver enzymes (ALT, AST), early fibrosis. Can resolve with sustained weight loss. Confirmed only by biopsy.

Fibrosis โ†’ Cirrhosis

Scar tissue forms, eventually replacing functional liver. Once cirrhosis is established, reversal is limited. Risk of liver failure, hepatocellular carcinoma, need for transplant. Early fibrosis can regress with sustained weight loss.

By the Numbers

NAFLD by the Numbers

~30%
of adults worldwide have NAFLD, now also called MASLD1
~56%
of people with type 2 diabetes worldwide have NAFLD, in 80 studies across 20 countries13
~58%
of biopsy-proven NASH patients who lost 5% or more of their weight had their NASH resolve2
โ‰ฅ10%
weight loss at which 90% of biopsy-proven NASH patients had their NASH resolve, and 45% had fibrosis regress2
3 to 5%
weight loss that improves liver fat; more than 10% is generally needed to improve NASH and fibrosis (AASLD)14
6.4ร—
higher risk of death from any cause with cirrhosis-stage fibrosis than with no fibrosis, in people with NAFLD15
Signs & Symptoms

Symptoms of NAFLD

NAFLD is silent in early stages. Most diagnoses happen incidentally on routine bloodwork or imaging. Symptoms only appear with NASH or advanced disease, by which point significant damage has occurred.

SymptomWhat happens
Common Symptoms
Unexplained FatigueMost common symptom in NAFLD. Persistent tiredness disproportionate to activity. Reflects mitochondrial dysfunction, chronic low-grade inflammation and impaired liver metabolism. Often dismissed as "stress."
Right Upper Quadrant DiscomfortVague achy fullness or pressure under the right rib cage. Reflects liver enlargement stretching its capsule. Often described as "I just feel a heaviness there." Not sharp pain (sharp = think gallbladder).
Stubborn Abdominal Weight GainVisceral fat correlates strongly with liver fat; they accumulate together. Waist circumference over 40 inches (102 cm) in men or 35 inches (88 cm) in women is a strong predictor of NAFLD even with "normal" BMI.
Brain Fog & Mental FatigueFatigue and trouble concentrating are commonly reported. In cirrhosis, sudden confusion is an emergency: call 911.
Advanced NAFLD / NASH Signs
Jaundice (Yellow Skin/Eyes)Yellow discoloration of skin or sclera (whites of eyes) indicates significant liver dysfunction. Late-stage sign suggesting advancement toward cirrhosis. Requires urgent evaluation.
Abdominal Swelling (Ascites)Fluid accumulation in abdomen, sign of advanced cirrhosis with portal hypertension. Significant abdominal distention not from food or fat. Always evaluated as serious.
Easy Bruising or BleedingThe liver makes clotting factors, so a failing liver impairs clotting. Easy bruising, prolonged bleeding from minor cuts or unexplained bleeding indicates advanced disease.
Spider Angiomas, Palmar ErythemaSmall spider-like blood vessels on the skin (especially face/chest) and reddened palms both reflect estrogen elevation when the liver can't metabolize hormones properly. Late-stage signs.
Causes

Causes of NAFLD

NAFLD is closely tied to weight, blood sugar, diet and activity, and genes make some people more prone to it16.

CauseHow It Contributes to NAFLDWhat Helps
Excess weight, especially around the waistBeing overweight, particularly with fat around the abdomen, raises the risk16; losing weight works the other way, and in 293 adults with NASH, losing 10% or more resolved it in 90%2Sustained weight loss through a calorie deficit, whichever eating pattern you can keep up, as the diet and treatment sections explain
Type 2 diabetes and insulin resistanceType 2 diabetes is an important risk factor and seems to speed liver disease progression13Blood sugar control with your clinician, weight loss and cutting refined carbohydrates as the diet section advises
Sugary drinksIn 12 studies of 35,705 people, drinking sugar-sweetened drinks was linked to 1.39 times the odds of NAFLD, rising with the amount17; in controlled trials, extra calories from sugary drinks produced large increases in liver fat18Cutting soda, juice and sweetened coffee or tea, as the diet section advises
Inactivity and diet qualityAn unhealthy diet or little physical activity raises the risk16Aerobic and resistance exercise, as the treatment section describes, and the food pattern in the diet section
AlcoholHeavy drinking speeds liver injury and scarring in people with NAFLD14Avoiding heavy drinking, and cutting alcohol as the diet section advises
GenesA common variant of the PNPLA3 gene is linked to more liver fat and inflammation; people with two copies had more than twice the liver fat of non-carriers19Genes cannot be changed; a family history of cirrhosis is one reason guidelines advise testing14
Diagnosis

How NAFLD Is Diagnosed

TestWhat it shows
Blood Tests
Liver Enzymes (ALT, AST, GGT)ALT (alanine aminotransferase) most specific for liver. An ALT above 30 U/L in men or 19 U/L in women, even inside the lab's normal range, can suggest liver fat. AST/ALT ratio >1 may indicate fibrosis. GGT also rises.
FIB-⁠4 ScoreNon-invasive fibrosis score calculated from age, ALT, AST, platelets. <1.3 low risk for advanced fibrosis; >2.67 high risk. Easy to calculate from routine labs; guidelines advise repeating it every 1 to 2 years in higher-risk people and every 2 to 3 years otherwise14.
Comprehensive Metabolic WorkupFasting insulin, HOMA-IR, HbA1c, lipid panel with triglycerides (often elevated), hs-CRP. NAFLD almost always coexists with insulin resistance, dyslipidemia and inflammation.
Imaging
Abdominal UltrasoundFirst-line imaging: fat shows as a bright (echogenic) liver on the scan. Cheap, accessible, no radiation. Against biopsy, it detected about 85% of moderate to severe fatty liver22; it can miss mild steatosis and cannot assess fibrosis. Often the first sign that triggers NAFLD diagnosis.
Transient ElastographyQuantifies both liver fat (CAP score) and fibrosis (kPa). CAP >238: mild steatosis; >260: moderate; >290: severe. Stiffness >7 kPa: significant fibrosis. Non-invasive, repeatable. Widely used for monitoring.
MRI-PDFFMost accurate non-invasive measurement of liver fat percentage. <5%: normal; 5 to 10%: mild; 10 to 15%: moderate; >15%: severe NAFLD. Expensive, less available. Excellent for tracking response to intervention.
Liver BiopsyHistorical gold standard but invasive. Only definitive diagnosis of NASH (vs simple steatosis) and accurate fibrosis staging. Reserved for high-risk patients or when imaging is inconclusive.
Treatment Comparison

Conventional and Holistic Treatment for NAFLD

๐ŸŒฟ HOLISTIC
๐Ÿ’Š CONVENTIONAL
๐ŸŒฟ

Holistic / Functional Approach

Low-carb/keto diet, intermittent fasting, fructose elimination, weight loss, exercise, targeted liver support

What Weight Loss Did
Weight loss of 10% or more resolved NASH in 90% of patients with biopsy-proven disease, and fibrosis regressed in 45%; 5% or more resolved NASH in 58%2
Diet Power
Carbohydrate restriction reduces liver fat, though reviews find the calorie deficit is the main driver rather than the macronutrient split3
Timeline
Liver tests and liver fat can improve within months of weight loss2
Advantage
Works on the drivers (insulin resistance, excess calories, refined carbs), and also improves diabetes, cholesterol, BP

Full Holistic Approach Includes

  • Cut added sugars and sugary drinks, the main source of excess fructose; fructose is metabolized mainly by the gut and liver, and excess becomes fat. Soda, juice, sweetened coffees and foods with high-fructose corn syrup are top culprits; whole fruit is fine.
  • Low-carbohydrate or ketogenic diet, one workable route: since the calorie deficit drives liver fat down, the best diet is the one you can sustain3. If you take medication for diabetes, agree on a low-carbohydrate change with your prescriber before starting: some newer diabetes medicines can cause ketoacidosis at normal blood-sugar readings when carbohydrate is cut sharply, and normal readings are exactly why it gets missed.
  • Time-restricted eating / intermittent fasting, 16:8 or 18:6 daily; gives liver time to process accumulated fat. On insulin or other diabetes medicine, agree on fasting with your prescriber first: skipped meals can cause low blood sugar28.
  • Mediterranean diet, the eating pattern liver guidelines recommend: olive oil, fatty fish, vegetables and whole grains in moderation.
  • Resistance + aerobic exercise: both reduce liver fat independently of weight loss. Aim for 150 min/week moderate aerobic + 2x/week resistance.
  • Weight loss target: 7 to 10% of body weight is the usual clinical goal, and larger losses give larger histological improvement2.
  • Berberine 500 mg 2 to 3x/day: activates AMPK, reduces hepatic fat synthesis, improves insulin sensitivity. Small trials, mostly from one region, report lower liver enzymes4; check interactions with your prescriber. Do not take it if you are pregnant or breastfeeding, as berberine can harm a newborn.
  • Milk thistle (silymarin) 420 mg/day, antioxidant, hepatoprotective. Trials report modest reductions in liver enzymes6.
  • Gut health: the gut-liver axis is implicated in NAFLD, and some probiotic and synbiotic trials report lower liver enzymes, with results varying by formulation10.
  • Vitamin E, the strongest single-supplement evidence for NASH, but with a narrow indication: the AASLD recommendation covers non-diabetic adults with biopsy-proven NASH only, and it carries prostate cancer and bleeding trade-offs. A hepatologist decision, not a self-directed supplement. See the supplement table below5.
โœ… Key point: NAFLD is one of the most lifestyle-responsive chronic diseases. In many patients, simple steatosis and early NASH improve substantially with weight loss and dietary change alone. Improvement becomes harder once advanced fibrosis sets in, so act early.
Supplement Protocol

Evidence-Based Supplements for NAFLD

These supplements target hepatic fat reduction, insulin sensitivity, antioxidant defense and gut-liver axis health.

SupplementWhat it is forTypical rangeTimingNotes & cautions
BerberineActivates AMPK, reduces hepatic fat synthesis and improves insulin sensitivity. Meta-analyses report reductions in liver enzymes and liver fat in NAFLD, though the trials are mostly small and largely conducted in one region, which limits how far the results generalize.4 Berberine interacts with many prescription medicines through CYP3A4 and P-glycoprotein, so check with your prescriber before starting it.500 mg 2 to 3x/dayWith mealsGI tolerance improves over 2 weeks. Don't combine with prescription diabetes meds without monitoring. Do not take it if you are pregnant or breastfeeding, as berberine can harm a newborn.
Vitamin EThis one has a narrow indication and real trade-offs, so read before considering it. The PIVENS trial found benefit in biopsy-proven NASH, and the AASLD recommendation is limited to non-diabetic adults with biopsy-proven NASH. PIVENS excluded people with type 2 diabetes, so there is no evidence base for this dose in that group, which matters here because a large share of people with NAFLD also have diabetes. Against the benefit: the SELECT trial found 400 IU/day raised prostate cancer risk in healthy men, a 2005 meta-analysis raised an all-cause mortality signal above 400 IU/day, and vitamin E inhibits platelet aggregation and can potentiate anticoagulants.5 This is a decision to make with a hepatologist, not a self-directed supplement.Specialist decision, and only for biopsy-proven NASH without diabetes. Not a self-directed supplement.With fat mealThe trial evidence is for vitamin E at 800 IU/day5; mixed tocopherols have not been shown to work better. Avoid in patients on anticoagulant medicines (consult prescriber).
Milk Thistle (Silymarin)A hepatoprotective antioxidant with a long safety record. Trials report modest reductions in ALT and AST in NAFLD, with liver fat and histology outcomes less consistent. Reasonable as an adjunct to dietary change rather than a treatment in its own right.6420 mg/day standardized silymarinWith mealsQuality varies; choose standardized extracts (80% silymarin). It may lower blood sugar in type 2 diabetes, so tell your prescriber if you take diabetes medicine, and avoid it if you are allergic to ragweed, chrysanthemum, marigold or daisy24.
Omega-⁠3 EPA/DHAReduces hepatic triglyceride accumulation and has anti-inflammatory effects. Meta-analyses support a modest reduction in liver fat, with less consistent effects on inflammation and fibrosis.72 to 4 g combined EPA+DHA/dayWith fat mealTriglyceride form. Third-party tested for purity. If you take a blood thinner, tell the clinician managing it before starting, as high doses can affect clotting25. Especially valuable if elevated triglycerides. In heart trials, fish oil supplements raised the risk of atrial fibrillation, an irregular heartbeat, more so above 1 g a day29, so check this dose with your clinician first.
Choline (Phosphatidylcholine)Choline is required to package fat into VLDL for export from the liver, and severe deficiency causes fat accumulation. That mechanism is well established; what is less clear is how often ordinary dietary shortfall drives NAFLD in practice, so treat choline as one contributing factor rather than a cause.8500 to 1,000 mg/dayWith mealsEggs are the richest dietary source. Sunflower lecithin is a good supplement form. Especially important on a low-egg diet.
N-Acetyl Cysteine (NAC)A glutathione precursor. Small trials report modest reductions in liver enzymes and oxidative stress markers in NAFLD. The evidence base is thin, so treat any specific figure as provisional.9600 to 1,200 mg/dayBetween mealsCan have sulfurous smell.
Probiotic / SynbioticThe gut-liver axis is genuinely implicated in NAFLD progression, and trials of specific strains report reductions in liver enzymes and improved insulin sensitivity. Effects vary substantially by formulation, so evidence for one product does not transfer to another.10Multi-strain 25 to 50 billion CFU + fermented foodsWith mealsHigh-strength multi-strain formulations have the most NAFLD-specific evidence.
Vitamin D3Deficiency very common in NAFLD; in a meta-analysis of 16 randomized trials in NAFLD, supplements lowered ALT, fasting blood sugar and insulin resistance, with no change in body fat26. Standard repletion approach.Set the dose with your clinician; most adults need no blood test firstWith fat mealThe adult upper intake level is 4,000 IU/day.
What to Expect

What to Expect Over Time

Weight loss and dietary change are the first-line treatment, alongside medical care for diabetes, blood pressure and cholesterol, and this is what the evidence shows about pace.

Treatment and supportive care, together
First Weeks

Liver fat can fall early with a calorie deficit: in 11 adults with type 2 diabetes on a supervised 600 kcal a day diet, liver fat fell from about 13% to 3% within 8 weeks20. A diet that strict needs medical supervision, especially on diabetes medication.

Months 1 to 3

Losing 3 to 5% of body weight improves liver fat14. If you take diabetes medication, agree on any low-carbohydrate change with your prescriber first, as the treatment section explains.

Months 3 to 12

In a 52-⁠week study of 293 adults with NASH, 58% of those who lost 5% or more had their NASH resolve, and with 10% or more, 90% did and 45% had fibrosis regress; only 30% reached 5%2.

Long Term

Fibrosis stage is what matters most, as the risk of liver-related death rises steeply with each stage15. Guidelines advise repeating a FIB-⁠4 fibrosis score every 1 to 2 years with prediabetes, diabetes or two or more metabolic risk factors, otherwise every 2 to 3 years14.

When to Seek Care

Call 911 for vomiting blood, very dark or black stools, or sudden confusion or slurred speech. Get an urgent appointment for yellow skin or eyes, a swollen abdomen, legs or ankles, or difficulty breathing21.

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Next Steps

Your Liver Responds Faster Than You Think

Liver fat responds quickly to dietary change: within weeks of a sustained calorie deficit it begins to fall20. Most patients can substantially improve early NAFLD with sustained weight loss and dietary change, which is the first-line treatment and works alongside medical care rather than replacing it.

Explore Diabetes โ†’ Explore High Cholesterol โ†’

References & Evidence Notes

Each numbered entry below is either a source you can follow or a note setting out what the evidence does and does not support. Both are numbered together so the markers in the text line up.

Last reviewed October 20, 2026. Supplement entries are cross-checked against the NIH National Center for Complementary and Integrative Health and the Linus Pauling Institute Micronutrient Information Center.11 This page is nutrition education, not medical advice, and it does not replace your doctor. Vitamin E at the doses discussed here is a specialist decision with real trade-offs, and berberine interacts with many prescription medicines. Discuss both with your prescriber before starting anything.

  1. Global prevalence of non-alcoholic fatty liver disease: an updated review and meta-analysis of 479 studies covering 78 million people across 38 countries, giving an adult prevalence of about 30.2%. 2024. PubMed 39094335. ↩ ↩ ↩
  2. Vilar-Gomez E, et al. Weight loss through lifestyle modification significantly reduces features of nonalcoholic steatohepatitis. Gastroenterology. 2015;149(2):367-⁠378. PubMed 25865049. In 293 patients with histologically proven NASH, followed with repeat biopsy after 52 weeks of lifestyle change: weight loss of 10% or more produced NASH resolution in 90% and fibrosis regression in 45%; 5% or more produced resolution in 58%. ↩
  3. Low fat diet versus low carbohydrate diet for management of non-alcoholic fatty liver disease: a systematic review. PMC9424761. See also the randomized comparison of intermittent calorie restriction against a low-carb high-fat diet, JHEP Reports. Both find the calorie deficit, not the macronutrient split, is the main driver. ↩ ↩
  4. Meta-analyses of berberine in NAFLD report reductions in liver enzymes and improvements in lipids and insulin sensitivity, PubMed 38429794; trials are mostly small and geographically concentrated. See also the interaction note in the NCCIH assessment, ref. 11. ↩
  5. Sanyal AJ, et al. The PIVENS trial comparing vitamin E, an insulin-sensitizing agent, and placebo in nonalcoholic steatohepatitis. N Engl J Med. 2010;362:1675-⁠1685, PubMed 20427778, which found vitamin E, given at 800 IU daily for 96 weeks, superior to placebo in adults without diabetes, and no benefit for the insulin-sensitizing comparator on the primary outcome. AASLD practice guidance limits the recommendation to non-diabetic adults with biopsy-proven NASH. On the risks: Klein EA, et al. Vitamin E and the risk of prostate cancer (SELECT). JAMA. 2011. jamanetwork.com; and Miller ER, et al., the 2005 meta-analysis reporting an all-cause mortality signal above 400 IU/day. ↩
  6. Silymarin trials in NAFLD report modest transaminase reductions with less consistent histological effect. See NCCIH, ref. 11. ↩
  7. Meta-analyses of omega-⁠3 supplementation in NAFLD report modest reductions in liver fat, with less consistent effects on inflammation and fibrosis. ↩
  8. Choline's role in VLDL assembly and hepatic fat export is well established; the contribution of ordinary dietary shortfall to NAFLD in practice is less clear. See the Linus Pauling Institute entry, ref. 11. ↩
  9. N-acetylcysteine trials in NAFLD are small and report modest transaminase changes. ↩
  10. Probiotic and synbiotic trials in NAFLD report reductions in liver enzymes and improved insulin sensitivity, with results varying substantially by formulation. ↩
  11. National Center for Complementary and Integrative Health (NIH), nccih.nih.gov, and the Linus Pauling Institute Micronutrient Information Center, lpi.oregonstate.edu/mic. ↩
  12. On the second approved NASH medicine: AASLD practice guidance reports that a GLP-⁠1 agonist received accelerated FDA approval in August 2025 for NASH with moderate to advanced fibrosis, stages F2 to F3, based on interim 72-⁠week trial results in which NASH resolved without worsening of fibrosis in 62.9% against 34.3% on placebo, and that final approval awaits long-term outcomes, PubMed 41201884. ↩
  13. On diabetes and NAFLD: a 2019 meta-analysis of 80 studies in 49,419 people with type 2 diabetes across 20 countries found NAFLD in 55.5% worldwide and 68.0% in European studies, and described type 2 diabetes as an important risk factor that seems to speed liver disease progression, PubMed 31279902. ↩
  14. On weight loss, alcohol and monitoring in NAFLD: AASLD practice guidance (2023) states that 3% to 5% weight loss improves liver fat but more than 10% is generally needed to improve NASH and fibrosis, that heavy alcohol use speeds liver injury and should be avoided, that testing should target people with type 2 diabetes, obesity with metabolic complications, a family history of cirrhosis or significant alcohol use, and that the FIB-⁠4 score be repeated every 1 to 2 years in higher-risk people and every 2 to 3 years otherwise, AASLD Practice Guidance, 2023. ↩
  15. On why fibrosis stage matters: a 2017 meta-analysis of biopsy studies in NAFLD found all-cause mortality rose with each fibrosis stage, to 6.4 times that of people without fibrosis at stage 4, and liver-related mortality rose exponentially, PubMed 28130788. ↩
  16. On who develops NAFLD and how it progresses: NHS guidance says most people only ever have the first stage, fatty liver, which does not usually cause problems, and a small number progress to the later stages with more serious liver damage. It lists being overweight, particularly with fat around the abdomen, an unhealthy diet or too little physical activity, type 2 diabetes, polycystic ovary syndrome, high blood pressure, high cholesterol and being over 50 as risk factors, NHS, non-alcoholic fatty liver disease. ↩
  17. On sugary drinks and NAFLD: a 2019 dose-response meta-analysis of 12 studies in 35,705 people found sugar-sweetened drink consumption linked to 1.39 times the odds of NAFLD, with risk rising with intake, PubMed 31234281. ↩
  18. On sugar and liver fat in trials: a 2022 meta-analysis of 51 controlled trials in 2,059 mostly healthy adults found that adding excess calories from sugar-sweetened drinks produced large increases in liver fat, with high certainty, while fructose-containing sugars exchanged for other foods at the same calories had no effect, PubMed 35889803. ↩
  19. On genes and NAFLD: a 2008 genome-wide study in Hispanic, African American and European American adults found a common PNPLA3 variant strongly linked to liver fat and inflammation, with more than twice the liver fat in people carrying two copies, PubMed 18820647. ↩
  20. On how fast liver fat can fall: in a 2011 study, 11 adults with type 2 diabetes followed a supervised 600 kcal a day diet for 8 weeks, and liver fat fell from 12.8% to 2.9%, PubMed 21656330. ↩
  21. On when to get help: NHS guidance for people with cirrhosis advises calling emergency services for vomiting blood, very dark or black stools, or sudden confusion or slurred speech, and an urgent appointment for yellow skin or eyes, difficulty breathing or a swollen belly, legs, ankles or feet, NHS, cirrhosis symptoms. ↩
  22. On ultrasound for fatty liver: a meta-analysis of 49 studies with 4,720 participants found that, against biopsy, ultrasound detected moderate to severe fatty liver with a sensitivity of 84.8% and a specificity of 93.6%, and concluded that it reliably detects moderate to severe fatty liver, PubMed 21618575. ↩
  23. On coffee and cirrhosis: a 2016 meta-analysis of five cohort and four case-control studies with 432,133 participants found that each extra 2 cups of coffee a day went with a 44% lower risk of cirrhosis (relative risk 0.56), and a similar reduction in death from cirrhosis. These are observational findings, PubMed 26806124. ↩
  24. On milk thistle safety: the NIH National Center for Complementary and Integrative Health reports that small studies suggest milk thistle may help control blood sugar in type 2 diabetes, that it may cause allergic reactions in people allergic to related plants such as ragweed, chrysanthemum, marigold and daisy, that some products contain far more or less silymarin than the label says, and that anyone taking medicine should talk with a clinician before using it, NCCIH, milk thistle. ↩
  25. On omega-⁠3 and blood thinners: the NIH Office of Dietary Supplements notes that fish oil can have antiplatelet effects at high doses and might prolong clotting times in people taking a vitamin K antagonist blood thinner, although most research finds 3 to 6 g a day does not significantly change anticoagulation, and that people taking omega-⁠3 products with anticoagulants should have the INR monitored periodically, NIH Office of Dietary Supplements. ↩
  26. On vitamin D in NAFLD: a 2021 meta-analysis of 16 randomized trials in people with NAFLD found vitamin D supplements lowered ALT, fasting blood sugar and insulin resistance and raised HDL cholesterol, with no significant change in body fat, triglycerides or total cholesterol, PubMed 34803681. ↩
  27. On NASH and liver transplants: in US transplant registry data from 2002 to 2019, NASH rose from 5% of waitlisted patients without liver cancer in 2002 to 28% in 2019, making it the second most common reason for a liver transplant after alcohol-related liver disease and the fastest increasing one, PubMed 32531342. ↩
  28. On fasting and diabetes medicine: MedlinePlus lists skipping meals, and not eating enough after taking insulin or diabetes medicine, among the causes of low blood sugar in people with diabetes, MedlinePlus, low blood sugar self-care. ↩
  29. Gencer B, Djousse L, Al-Ramady OT, Cook NR, Manson JE, Albert CM. Effect of long-term marine omega-⁠3 fatty acids supplementation on the risk of atrial fibrillation in randomized controlled trials of cardiovascular outcomes: a systematic review and meta-analysis. Circulation. 2021;144(25):1981-⁠1990. PubMed 34612056. Seven trials with 81,210 people followed for about 5 years: omega-⁠3 supplements were linked to a higher risk of atrial fibrillation (hazard ratio 1.25), more so in trials of more than 1 g a day (1.49), and the risk rose with each additional gram. ↩