Fructose and the link to the metabolic syndrome

Piero Portincasa, MD, PhDLeonilde Bonfrate,MD

Department of Internal and Public MedicineUniversity of Bari Medical School

Bari – Italyp.portincasa@semeiotica.uniba.it

Metabolic Syndrome

ObesityDiabetes

Dyslipidemia

EPIDEMIA DEL III MILLENNIO

NAFLD: Associated with Metabolic Syndrome

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The “BOTERO Syndrome”

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Food fast!

Fast food!

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FRUITS AND VEGETABLES 17/09/12

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FRUITS AND VEGETABLES

• Consumption is inversely related to the risk of coronary heart disease (CHD) and stroke

The effect of fruit and vegetable intake on risk for coronary heart disease. AU Joshipura KJ; Hu FB; Manson JE; Stampfer MJ; Rimm EB; Speizer FE; Colditz G; Ascherio A; Rosner B; Spiegelman D; Willett WC SO Ann Intern Med 2001 Jun 19;134(12):1106-14.

Legume consumption and risk of coronary heart disease in US men and women: NHANES I Epidemiologic Follow-up Study. AU Bazzano LA; He J; Ogden LG; Loria C; Vupputuri S; Myers L; Whelton PK SO Arch Intern Med 2001 Nov 26;161(21):2573-8.    

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The effect of fruit and vegetable intake on risk for coronary heart disease. AU Joshipura KJ; Hu FB; Manson JE; Stampfer MJ; Rimm EB; Speizer FE; Colditz G; Ascherio A; Rosner B; Spiegelman D; Willett WC SO Ann Intern Med 2001 Jun 19;134(12):1106-14.

• The Nurses' Health Study and the Health Professionals' Follow-Up Study

• 84 251 women 34 to 59 yrs of age who for 14 yrs and 42 148 men 40 to 75 yrs followed for 8 yrs

• Incidence of nonfatal myocardial infarction or fatal coronary heart disease (1127 cases in women and 1063 cases in men).

• Diet assessed by using food-frequency questionnaires

• CONCLUSIONS: Consumption of fruits and vegetables, particularly green leafy vegetables and vitamin C-rich fruits and vegetables, appears to have a protective effect against coronary heart disease

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Fruit and vegetable consumption and stroke: meta-analysis of cohort studies. He FJ; Nowson CA; MacGregor GA Lancet. 2006 Jan 28;367(9507):320-6.  

• MEDLINE, EMBASE, the Cochrane Library, and bibliographies of retrieved articles

• 8 studies, 9 independent cohorts• 257,551 individuals (4917 stroke events), average

follow-up of 13 years• relative risk of stroke was 0.89 (95% CI 0.83-0.97) for

those with 3 to 5 servings per day, and 0.74 (0.69-0.79) >5 servings per day.

• Fruit and vegetables significant protective effect on both ischaemic and haemorrhagic stroke.

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Lyn M Steffen Jan 28, 2006, The Lancet, Vol. 367 No. 9507 pp 278-279

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5 a day!

Lancet. 2006 Jan 28;367(9507):320-6.  

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FRUCTOSE........FRIEND… OR ENEMY?

16–20 grams/day (only fresh fruits)

85–100 grams/day

74%

Fructose consumption

Basciano et al; Nutr Metab (Lond). 2005; 2: 5.

Dietary fructose

Fructose • a free hexose• as the disaccharide (sucrose:

glucose-fructose)• in a polymerized form (fructans)

Up to one half of the population unable to completely absorb a load of 25 g

4 Kcal / g Glycemic index: 23 (sucrose:

57)

monosaccharide

sucrose

OH

OHHO

O

HO OH

Chemical Formula: C6H12O6Exact Mass: 180.1

Molecular Weight: 180.2

O

HOHO

OH

OH

O

OH

OOH

OH

OH

Chemical Formula: C18H34O17Exact Mass: 522.2

Molecular Weight: 522.5

Food Fructose (grams / 100 grams)

Glucose (grams / 100 grams)

High fructosecorn syrup 55 to 90 45 to 10

Sucrose(for reference) 50 50

Honey 40.9 35.7

Raisins 29.8 27.8

Pears 6.2 2.8

Apples 5.9 2.4

Fruit juicee.g. Apples,

Pears5 to 7 2 to 3

Watermelon 3.4 1.6

According to the USDA database, foods with more fructose than glucose include:

Metabolic pathways of entry of (A) glucose and (B) fructose into the glycolytic pathway

of the CNS

Cha S H et al. PNAS 2008;105:16871-16875

©2008 by National Academy of Sciences

Central administration of fructose

Fructose exerts an orexigenic effect

Seung Hun Cha et al., Proc Natl Acad Sci U S A. November 2008

FRUCTOSE IN THE LIVER

A high flux of fructose to the liver (the main organ capable of metabolizing this simple

carbohydrate)

1. perturbs glucose metabolism and glucose uptake pathways (Fructose-induced insulin resistance)

2. leads to a significantly enhanced rate of de novo lipogenesis and triglyceride (TG) synthesis, driven by the high flux of glycerol and acyl portions of TG molecules from fructose catabolism.

Basciano et al. Nutr Metab (Lond). 2005; 2: 5.

MTP (microsomial triglyceride transfer protein)

Increased fructose intake

upregulation of KHK (fructokinase)

fructose-induced ATP depletion

Hepatic necroinflammation

NAFLD

keypointsHigh dietary

intake of fructose

metabolic syndrome

dyslipidemia

insulin resistance

NAFLD