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How Fructose Drives Metabolic Disease | Rick Johnson, M.D. — Whalespan

Content›Video›How Fructose Drives Metaboli…

How Fructose Drives Metabolic Disease | Rick Johnson, M.D.

Peter Attia2h 24m · 2022-02-07

Support Rate

79%

172 of 219 claims supported

Support rate

172 of 219 claims supported

172 supported47 partial / not

Claims from this content

181

✓Well SupportedModerate amounts of fructose, up to 1 gram per kilogram of body weight, can be processed without arriving in the liver.✓Well SupportedAnimals with a fructokinase knockout gain less weight than normal animals when given glucose alone.✓Well SupportedA diet low in refined sugar and high-fructose corn syrup, which either restricts or includes natural fruits, can lead to equivalent improvements in metabolic syndrome.✓Well SupportedThere is a linear relationship between blood pressure and the risk of stroke and heart failure, extending down to 120/80 mmHg.✓Well SupportedFructose causes fatty liver and metabolic syndrome in mice even without causing weight gain when food intake is controlled.

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Bookmarking — the dossier-vs-overview split is the right call. Most of the time I want overview; sometimes I want receipts.

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✓Well SupportedA glomerular filtration rate (GFR) at 80% of predicted in one's 40s suggests a future decline that needs to be considered for long-term longevity.

✓Well SupportedFructose metabolism can activate the Warburg effect in some cancers, leading to decreased ATP and increased glucose influx.

✓Well SupportedBlood pressure levels between 160-180 mmHg significantly increase the risk of stroke and mortality due to the body's autoregulation mechanisms being overcome.

✓Well SupportedSome sports drinks contain more fructose than optimal because it improves taste, which can be problematic if consumed outside of exercise.

✓Well SupportedA person with blood pressure of 135/85 mmHg will have lower renal function at the end of life compared to someone with 120/80 mmHg.

✓Well SupportedATP depletion from fructose metabolism leads to a fall in intracellular phosphate, activating AMP deaminase.

✓Well SupportedLeptin resistance in overweight humans is primarily at the hypothalamic level, leading to high leptin levels that fail to signal fullness.

✓Well SupportedFructose metabolism consumes ATP and generates uric acid.

✓Well SupportedFructose consumption leads to insulin resistance, fatty liver, and hypertension, even when calorie intake is controlled.

✓Well SupportedBy the late 30s or early 40s, any ApoB level above the 20th percentile (approximately 80 mg/dL) should be aggressively lowered.

◐Partially SupportedThe rate-limiting enzyme in converting glucose to sorbitol is aldo-reductase, which can be induced by high glucose and high uric acid.

✓Well SupportedFor patients with non-alcoholic fatty liver disease, restricting fructose intake to 10 grams per day, solely from whole fruit, is a reasonable approach.

◐Partially SupportedHypertension is defined as blood pressure greater than 140/90 mmHg globally, and greater than 130/80 mmHg in the United States.

✓Well SupportedFructose from whole fruits like berries or bananas is better than fructose in juice form due to fiber content slowing glucose spikes.

✓Well SupportedSports drinks containing lactate, glucose, and fructose are superior to those with high-fructose corn syrup and insufficient glucose for quick energy.

◐Partially SupportedDried fruit is metabolically similar to candy when consumed in equivalent calorie amounts to fresh fruit because beneficial components are removed.

◐Partially SupportedConsuming sugar or fructose acutely raises blood pressure in humans within minutes.

◐Partially SupportedMice consuming glucose or fructose in their drinking water increase their water intake, leading to a significant caloric intake from the sugar-sweetened beverages.

✓Well SupportedAdded sugars like sucrose or high-fructose corn syrup are deliberately added to foods to increase sweetness.

◐Partially SupportedWhen the gut is exposed to higher concentrations of fructose, it bypasses gut metabolism and enters the portal system, preferentially reaching the liver.

◐Partially SupportedThe Pediatric Society recommends limiting fruit juice intake to 6 ounces or less for older children and 4 ounces or less for younger children due to its high fructose content being associated with childhood obesity.

◐Partially SupportedMice with a fructokinase knockout do not develop a preference for sugar and do not gain fat even when forced to consume fructose.

◐Partially SupportedFruits and vegetables with low fructose content (2-5 grams) do not cause energy depletion because intestinal fructokinase inactivates small amounts.

◐Partially SupportedFruits like kiwi, berries, strawberries, and blueberries are low in sugar and healthy.

◐Partially SupportedHigh blood pressure is a major cause of stroke, heart failure, and kidney disease.

◐Partially SupportedA blood pressure of 140/90 mmHg is a reasonable cutoff for viewing hypertension as a condition requiring active management.

◐Partially SupportedReducing food intake leads to less oxidative stress and fat storage, potentially increasing lifespan.

◐Partially SupportedA single, real orange contains approximately 6-8 grams of fructose.

◐Partially SupportedObesity is driven by biological pathways that increase food intake and decrease physical activity.

◐Partially SupportedNutritional and exercise interventions, such as reducing salt intake and healthier food choices, should be the primary approach for blood pressure of 135/85 mmHg.

✓Well SupportedIn animals that cannot metabolize fructose, salt intake does not lead to obesity, hypertension, or left ventricular hypertrophy.

◐Partially SupportedIndividuals with essential fructosuria, who lack fructokinase, have not been reported to have type 2 diabetes or obesity and appear to have normal or prolonged lifespan.

◐Partially SupportedRecurrent chronic oxidative stress to mitochondria is strongly implicated in age-related decline of mitochondrial function.

◐Partially SupportedLiquid fructose absorbed rapidly on an empty stomach leads to higher concentrations in the liver and exacerbates ATP depletion.

◐Partially SupportedHigh uric acid can drive kidney inflammation, leading to reduced blood flow, salt retention, and high blood pressure.

◐Partially SupportedIf blood pressure cannot be lowered below 140/90 mmHg through diet, antihypertensive medication should be considered.

◐Partially SupportedChronic stimulation of mitochondrial oxidative stress, particularly from fructose, decreases the number and efficiency of mitochondria, resulting in reduced ATP production and fatigue.

◐Partially SupportedMitochondrial dysfunction is a hallmark of aging due to reduced ATP production from oxidative stress damage.

◐Partially SupportedMitochondrial function can be quantified in animals using methods like electron microscopy, PCR for mitochondrial DNA, and ATP level measurements.

◐Partially SupportedEli Lilly is conducting Phase 1 trials for their fructokinase inhibitor.

◐Partially SupportedReduced ATP levels due to decreased mitochondrial function are associated with fatigue, muscle fatigue, and a slower natural gait.

◐Partially SupportedMitochondria are the primary high-output energy producers in the body, generating ATP necessary for all functions.

◐Partially SupportedA high fructose diet in men increased blood pressure and led to metabolic syndrome in 25% of participants.

◐Partially SupportedIn high glucose states, the polyol pathway enzyme converts glucose to sorbitol, which is then converted to fructose.

✓Well SupportedThe human body can produce excess fructose from glucose when hyperglycemic.

✓Well SupportedSalt and sugar increase blood osmolality, stimulating vasopressin release.

◐Partially SupportedLiquid sources of fructose, such as smoothies and sugar-sweetened beverages, should be eliminated for individuals with or at risk for NAFLD.

◐Partially SupportedIn animals, glucose consumption leads to metabolic syndrome features like insulin resistance and fatty liver.

◐Partially SupportedThe enzyme ketohexokinase phosphorylates fructose to fructose 1-phosphate, which rapidly drops cellular ATP levels.

◐Partially SupportedAdministering a uricase inhibitor to animals caused high blood pressure, which was lowered by reducing uric acid.

✕Not SupportedDefining hypertension at lower blood pressure levels implies the use of antihypertensives for which the evidence is not strong enough.

◐Partially SupportedPfizer stopped the progression of their fructokinase inhibitor drug despite positive Phase 2 results and no reported toxicity.

◐Partially SupportedFasting and caloric restriction are thought to promote longevity by reducing mitochondrial oxidative stress and potentially increasing mitochondrial biogenesis.

◐Partially SupportedFrench fries are particularly fattening because the combination of salt and carbohydrates strongly activates the fructose-producing pathway.

◐Partially SupportedIndividuals with essential fructosuria do not have a taste preference for sugar and tend to prefer salty foods over sugary ones.

◐Partially SupportedChildren with obesity and biopsy-proven fatty liver absorbed 100% of a fructose dose and metabolized it faster than lean children or obese children without fatty liver.

◐Partially SupportedIncreased salt concentration in the blood activates the polyol pathway enzyme aldose reductase, converting glucose to fructose.

✕Not SupportedThe high fructose corn syrup industry uses short-term, isocaloric study findings to claim sugar is safe, but this misses the point that sugar itself causes hunger.

✓Well SupportedOptimizing health through lifestyle measures is the best strategy to maintain health for the longest possible duration.

◐Partially SupportedHigh salt intake increases the risk for fatty liver and diabetes.

◐Partially SupportedLow levels of obesity (BMI of ~27) appear protective in individuals with chronic diseases like cancer or heart failure, compared to a BMI of 20.

◐Partially SupportedFructose metabolism leads to uric acid formation through the degradation of adenosine components.

◐Partially SupportedElevated glucose concentration can activate aldose reductase, converting glucose to fructose due to its osmolar load.

◐Partially SupportedMitochondrial oxidative stress, stimulated by fructose, is required for fat storage.

◐Partially SupportedA low-fructose diet can increase mitochondrial biogenesis in humans within 30 days.

◐Partially SupportedMost fruits contain between 3 and 10 grams of sugar.

✕Not SupportedThere is insufficient evidence to support the long-term benefit of antihypertensives for individuals with blood pressure around 135/85.

◐Partially SupportedThe vasopressin V1b receptor stimulates ACTH production, cortisol release, glucagon production, and upregulates hepatic fructose pathways.

◐Partially SupportedFructokinase is present in various tissues and can be induced in the heart or kidney following injury or failure.

◐Partially SupportedHigh salt intake in animals stimulates fructose production, leading to hypertension and metabolic syndrome.

✓Well SupportedHigh glycemic carbohydrates are a primary food source that the body uses to generate fructose internally, especially when the polyol pathway is active.

◐Partially SupportedThe intestine can protect the liver from up to 4-6 grams of fructose by slowing absorption, especially when fiber is present in whole fruits.

◐Partially SupportedAvoiding drinking sugar and added sugar is key for improving metabolic syndrome, while natural fruits are permissible.

✓Well SupportedYoung individuals have healthier mitochondria and greater metabolic flexibility, allowing easier metabolism of substances like sugar.

◐Partially SupportedIncreased sugar exposure enhances fructose absorption and metabolism by upregulating specific enzymes and transporters.

◐Partially SupportedFructose ingestion can lead to weight gain by increasing energy intake and decreasing energy expenditure.

◐Partially SupportedDrinking sufficient water can blunt the blood pressure-raising effect of salt.

✓Well SupportedReducing salt intake and maintaining high potassium intake are important dietary modifications for individuals with hypertension.

◐Partially SupportedThe greatest risk factor for high blood pressure is the salt concentration in the blood, not necessarily the amount consumed.

◐Partially SupportedFructokinase knockout mice showed a smaller rise in blood pressure when given salt compared to normal mice.

◐Partially SupportedDietary measures, including reducing salt and choosing healthier foods, can help manage blood pressure.

◐Partially SupportedA diet with 40% sugar versus starch did not result in significant weight difference in a calorie-controlled study.

◐Partially SupportedFructose metabolism drives metabolic disease by lowering cellular energy levels through fructokinase activation, depleting ATP.

◐Partially SupportedIn isocaloric studies, hunger without the ability to eat more masks the weight-gain effect of sugar.

◐Partially SupportedVasopressin, stimulated by fructose, drives obesity and metabolic syndrome.

◐Partially SupportedFructose stimulates obesity and metabolic syndrome by encouraging increased food intake and positive energy balance.

◐Partially SupportedReducing insulin resistance and metabolic syndrome through lifestyle interventions is a primary treatment for hypertension.

◐Partially SupportedThe cellular response to stress, characterized by reduced energy and fat/glycogen storage, mimics starvation and triggers a survival alarm signal.

◐Partially SupportedDried fruit is less satiating than whole fruit because the water content is removed, making it easier to overconsume.

◐Partially SupportedAnimals fed a high-sugar diet developed diabetes and fatty liver, unlike those fed starch.

◐Partially SupportedHigh doses of fructose can pass through the intestine, causing ATP injury to intestinal cells, leading to gut leak and potentially food allergies.

◐Partially SupportedThe book 'Nature Wants Us to Be Fat' discusses fructose metabolism, uric acid, and the vasopressin link.

◐Partially SupportedUric acid causes oxidative stress to mitochondria, inhibiting the Krebs cycle and leading to increased fat production.

◐Partially SupportedThe average American consumes 75-100 grams of fructose per day.

◐Partially SupportedHealthy mitochondria in young individuals and athletes can better resist the metabolic effects of fructose.

◐Partially SupportedFreshly squeezed orange juice and apple juice can contain significant amounts of sugar, with apple juice being equivalent to a soft drink in sugar content.

◐Partially SupportedPost-menopause, women experience increased uric acid levels, leading to a higher incidence of obesity, diabetes, and heart disease.

◐Partially SupportedIn the liver, fructose is phosphorylated to fructose-1-phosphate, leading to a depletion of ATP and an increase in ADP and AMP.

◐Partially SupportedMice lacking fructose metabolism had statistically significantly leaner body composition compared to non-fructokinase wild-type mice.

◐Partially SupportedHigh glucose activating aldo-reductase is a pathway implicated in diabetic complications.

◐Partially SupportedStress inhibits 'econotase', leading to citrate accumulation, stimulation of fat production, blocking of beta-fatty acid oxidation, reduced ATP production, and promoting fat storage.

◐Partially SupportedThe biological system is engineered for a food-scarce environment, where enzymes activated by fructose signal the organism to consume more, inhibit fat oxidation, and promote fat storage.

◐Partially SupportedWhen animals are given fructose or glucose in their drinking water, they initially drink more and reduce food intake, but over weeks to months, they begin eating more, leading to obesity.

◐Partially SupportedIsochoric fructose restriction may lead to improvements in fatty liver.

◐Partially SupportedFat metabolism generates water that animals use as a source of hydration.

◐Partially SupportedDried fruit has lower levels of vitamin C compared to fresh fruit.

◐Partially SupportedLeptin resistance, characterized by high leptin levels that do not signal satiety to the brain, is a mechanism by which fructose causes animals to eat more.

◐Partially SupportedUric acid from fructose metabolism inhibits beta-oxidation and increases de novo lipogenesis.

◐Partially SupportedThe induction of aldo-reductase by uric acid has been shown in animal and cell culture studies, and is believed to be likely true in humans.

◐Partially SupportedFructose metabolism in modern diets with high sugar intake is hazardous to human health.

◐Partially SupportedTo reduce fructose intake, avoid drinking soft drinks and fruit juices.

◐Partially SupportedSalt sensitivity and its effect on blood pressure increase with age.

◐Partially SupportedConsuming a soft drink can increase endogenous fructose production by three to fourfold.

◐Partially SupportedMetabolic derangement, not obesity itself, is the root cause of mortality and is highly correlated with obesity.

◐Partially SupportedIncreased sugar consumption leads to increased sugar absorption in animals, a phenomenon believed to carry over to humans.

◐Partially SupportedSorbitol is considered an artificial sweetener.

◐Partially SupportedWeight gain from sugar is primarily due to increased energy intake, with a smaller contribution from decreased energy metabolism.

◐Partially SupportedReversing NAFLD can occur without significant weight loss when fructose and alcohol are restricted.

✕Not SupportedDried fruit retains fructose but loses beneficial components like vitamin C, potassium, flavonols, and epicatechin.

◐Partially SupportedMice genetically modified to lack fructose metabolism remained leaner with normal or lower blood pressure over two years when fed a standard low-fructose chow.

◐Partially SupportedA BMI of 27-28 may be more protective than a BMI of 20-24 as people age.

◐Partially SupportedA glomerular filtration rate (GFR) of 87 is insufficient for a 40-year-old woman aiming for a GFR of 40 at age 100, with an ideal GFR of 107.

◐Partially SupportedSalt intake significantly impacts blood pressure, with sensitivity increasing with age.

◐Partially SupportedThe enzyme that converts glucose to fructose is present in very small amounts in the liver at birth but is induced over time.

◐Partially SupportedIn mice, fructokinase knockout animals showed no kidney aging changes compared to normal mice.

◐Partially SupportedStress inhibits AMP-activated protein kinase, which is activated during starvation to raise energy levels.

◐Partially SupportedOriginal sports drinks were developed to replenish electrolytes and provide glucose during exercise, containing glucose and salt.

◐Partially SupportedSports drinks are acceptable during strenuous exercise but not for sedentary consumption.

◐Partially SupportedAnimals with the V1b receptor knocked out show a preference for salt over sugar and appear protected from obesity.

◐Partially SupportedThe V1b receptor stimulates ACTH to produce cortisol, stimulates the pancreas to produce glucagon, and upregulates fructose pathways in the liver.

◐Partially SupportedGlucose levels in the liver are likely higher than in the blood due to the liver's first-pass metabolism of ingested carbohydrates.

◐Partially SupportedUric acid stimulates mitochondrial oxidative stress by activating NADPH oxidase, inhibiting fatty acid oxidation and leading to fat synthesis.

◐Partially SupportedMice with a blocked V1b receptor do not become obese, develop fatty liver, or become insulin resistant despite high sugar intake.

◐Partially SupportedPatients with NAFLD who consumed large amounts of soft drinks showed high uric acid levels and a three to fourfold increase in liver fructokinase expression.

◐Partially SupportedChronic consumption of salt in animals leads to high blood pressure, heart hypertrophy, metabolic syndrome, obesity, and insulin resistance.

◐Partially SupportedUric acid raises blood pressure directly by inhibiting nitric oxide production and stimulating oxidative stress.

◐Partially SupportedHigh salt intake in humans increases the risk for obesity and insulin resistance, in addition to hypertension.

◐Partially SupportedAchieving a GFR of at least 40 at age 100 may require revising current standards for hypertension management.

◐Partially SupportedHigh blood pressure is initiated by consuming foods high in salt and sugar.

◐Partially SupportedChronically elevated blood pressure requires inflammation in the kidney, which is associated with high uric acid.

◐Partially SupportedA reduction in diastolic blood pressure of more than 3 mmHg or systolic blood pressure of more than 4-5 mmHg is considered clinically significant.

◐Partially SupportedUric acid reduces endothelial nitric oxide by binding to it, decreasing L-arginine uptake, and potentially blocking endothelial nitric oxide synthase.

◐Partially SupportedEating a whole orange is unlikely to be detrimental to health, except possibly for individuals with NAFLD.

◐Partially SupportedFructose metabolism activates metabolic processes that lead to diabetes, obesity, and hypertension, driven by a side chain reaction rather than just its caloric content.

◐Partially SupportedThe liver is the primary organ involved in metabolic syndrome, the kidney in kidney disease, and the brain in Alzheimer's disease.

◐Partially SupportedAn assay could be developed to measure aldo-reductase activity in peripheral blood to indicate elevated levels in the liver, suggesting bread is more fattening.

◐Partially SupportedThe liver sequesters and metabolizes glucose, with only a portion entering the bloodstream, making blood glucose levels an indicator of a larger internal pool.

◐Partially SupportedIn one study, 25% of participants who did not receive allopurinol developed metabolic syndrome de novo, primarily due to a significant rise in blood pressure.

◐Partially SupportedFructose metabolism generates uric acid, which promotes further fructose metabolism in a positive feedback loop.

◐Partially SupportedSorbitol levels in plasma can serve as a marker for the activation of the glucose to sorbitol pathway.

◐Partially SupportedMenopause is believed to be related to changes in uric acid levels.

◐Partially SupportedLowering uric acid with allopurinol normalized blood pressure in 90% of adolescents with newly discovered hypertension.

◐Partially SupportedEssential fructosuria is a hereditary condition where individuals lack fructokinase, causing 10% of ingested fructose to be excreted in urine.

◐Partially SupportedConsuming sucrose leads to obesity, insulin resistance, and premature death from complications related to uric acid production and kidney failure in fruit flies.

◐Partially SupportedMice with a V1b receptor knockout maintain normal weight and do not develop metabolic syndrome because they do not upregulate fructokinase levels in response to sugar.

◐Partially SupportedUric acid may contribute to leptin resistance by causing inflammation in the hypothalamus.

◐Partially SupportedA 5-8 mmHg drop in systolic blood pressure and a 3-5 mmHg drop in diastolic blood pressure is considered clinically significant and associated with reduced cardiovascular events.

◐Partially SupportedHigh blood pressure is a significant risk factor for neurodegenerative disease, cardiovascular disease, cerebrovascular disease, and renal disease.

◐Partially SupportedFructose stimulates obesity and metabolic syndrome by increasing hunger, promoting leptin resistance, and decreasing energy metabolism.

◐Partially SupportedUric acid inhibits enol-a-hydratase, blocking the burning of fatty acids and promoting fat storage.

◐Partially SupportedActivation of the polyol pathway and increased aldose reductase expression in the liver can lead to greater weight gain from high glycemic foods as people age.

◐Partially SupportedEndogenous fructose production can contribute an additional 25-50% on top of exogenous fructose consumption in individuals with insulin and leptin resistance.

◐Partially SupportedFructose has numerous metabolic effects independent of its caloric content, driven by an energy depletion pathway that stimulates food intake and contributes to obesity.

◐Partially SupportedComparing fructose to glucose in studies is not a fair comparison because glucose can be converted to fructose in the body.

◐Partially SupportedHigh fructose corn syrup may be absorbed differently than sucrose because the fructose and glucose are already separated.

◐Partially SupportedExcess fructose does not alter energy expenditure in a clinically relevant manner in calorie-controlled states.

◐Partially SupportedHigh glycemic carbohydrates like rice, potatoes, and bread can be converted into fructose in the body, contributing to metabolic syndrome.

◐Partially SupportedHigh blood pressure in kidneys is associated with low-grade inflammation driven by T cells and macrophages, which reduces blood flow and impairs salt excretion.

◐Partially SupportedMitochondrial function decreases with age, shown by fewer and smaller mitochondria per gram of muscle in biopsies.

◐Partially SupportedReducing mitochondrial oxidative stress may promote longevity.

◐Partially SupportedEndogenous fructose production may play a significant role in the aging process.

◐Partially SupportedHigh glycemic foods like bread, rice, potatoes, chips, and cereals cause significant rises in blood and liver glucose concentrations.

◐Partially SupportedOsmolality activates aldose reductase via the transcription factor tony bp binding to an osmo-sensitive region in the enzyme's promoter.

◐Partially SupportedVasopressin levels are high during fat storage but plummet during hibernation, allowing hibernating animals to burn fat.

◐Partially SupportedLeptin resistance can be diagnosed in animal studies by observing a lack of reduced food intake after leptin injection.

◐Partially SupportedUric acid levels over 7 mg/dL may activate the aldo-reductase pathway, leading to de novo fructose production, and are common in metabolic syndrome.