Focus on the benefits and the risks connected to the meat consumption, CVD desease and policyclic aromatic compounds produced in cooking time

1. Martin Lemke – Lorenzo Cinetto - Lorenzo Bandinelli
Meat consumption
Benefit or Risk?
1. Harris, L. K. et al. 2013, Bioaccessibility of polycyclic aromatic hydrocarbons: relevance to toxicity and
carcinogenesis. Expert Opinion on Drug Metabolism & Toxicology 9(11): 1465–1480
2. Hamidi, N. E. et al. 2016, Polycyclic aromatic hydrocarbons(PAHs) and their bioaccessibilty in meat: a tool for
aassessing human cancer risk. Asian pacific journal of cancer prevention, volume 17. page 15-23

3. Red and processed meat associated to : CVD and Colon Cancer
Responsible : Fat content
Fatty acid composition
Formation of carcinogenic compounds  Polycyclic aromatic hydrocarbons
 methodological issue!!
…But factors influencing meat consumption are :
 Sex – Age – Religion – BMI – Physical activity
UK and Ireland vs South of Europe
Irish : 88% meat consumption
Men Women
Beef 39,1 g/d 46,8 g/d 30,5g/d
Lamb 22,8 g/d 28,1 g/d 16,9 g/d
• Higher consumption of meat in south of Europe, but lower incidence of CVD and colon cancer
• UK last 20 years consumption of red meat decline, but incidence of cancer is increasing
Paradox?
• Problems

4. Polycyclic Aromatic
Hydrocarbons (PAHs)
Heterocyclic Aromatic
Amines (HAAs)
Major compounds
www.users.humboldt.eduwww.astrochem.org
• Excursus – formation of
carcinogenic compounds

5. Polycyclic Aromatic
Hydrocarbons(PAHs)
Formed during thermal treatment of food
Environmental pollutants produced by
pyrolysis or incomplete combustion of
organic materials
15 were classified to be most
carcinogenic, cytotoxic and mutagenic
• Excursus – formation of
carcinogenic compounds

6. Source: Hamidi, N. E. et al. 2016
• Human Exposure to PAHs…

7. Bioaccessibility=
estimate amount of
toxicants after
digestion which is
potentially
bioavailable
Bioavailability=
available toxicants in
the body
Source: Harris, L. K. et al. 20132
• …depends on the bioaccessiblity of
food contaminants

8. • Colon Cancer
Truswell : in 20/30 cases of colon cancer ,no association with red meat
• Divide colon cancer and colorectal cancer  risk only for distal colon (sometimes)
• Other issue : distinction from red and processed meat
- Larson found risks in Bacon, hot dog and ham
• The proposed canceroginity of meat depends from :• The method of cooking
• Quantinty consumed
• Individual genetic risk
Method of cooking produces :
-PAHs and HCAs compounds  released also with cooking vegetables
Aproximatively :
 80% of colon cancer cases are thought to be caused by modifiable diet and lifestyle
 Improbable red meat as a foundamental role in colon cancer , there are other factors
- Smoking, lifestyle, physical activity level, cooking way….

9. Diet : one of the modifiable
factors for CVD
 Coronary Heart Disease (CHD)
 Stroke
 Myocardical infarction
In the past red meat associated to CHD
-Results no signidìficants , the lifestyle of people was not associate on it
(Alcohol, smoke, family history CHD etc..)
2008 Kontagianni : high consumption  acute coronary syndrome
low intakes  no associations 60 g/d
… To have a good evaluation is to consider the overall lifestyle of people !!!
E.g.
Typical Western Dietary Pattern:
-High red meat
-Low fruits and vegetables  Associated 
-High alcohol intake
-Low levels of Physical activity
22% risk in mortality from CVD than a
diet with moderate consumption of fruit
and vegetables, puoltry, legumes and
whole grains
• CVD• CVD

10. • Fat saturated and trans fatty acids
To reduce CVD low SFA and Trans fatty acid
Major SFA in Beef :
Myristic (C14:00)
Palmitic (C16:00)
Stearic (C18:00)
 Cholesterolum
 Higher plasma concentration of cholesterolum
 Low Density Lipoprotein (LDL)
 Triglycerides (TG)
This for high consumers 285 g/d
…Than Vegetarians…
Cross sectional studies (24-74 g/day)  14% total SFA among Irish
Today meat in leaner than 10 years ago, now SFA is – 5%
• Poultry and fish instead of red meat  failed
Trans Fatty Acids  incease the concentration of cholesterol…
…maybe industrial products !!
Trans Vaccenic Acid (TVA) major fatty acid in red meat
-no effect in cholesterol
-no effect in LDL cholesterol concentrations
Intermediate to produce CLA
(cis 9 trans 11)
-it has a lot of benefits

11. • Benefit to Health
50% of fat in Beef and Lamb are PUFA  MUFA : oleic acid
PUFA : n-6 linoleic acid (C18:2)
n-3 alphalinolenic acid (C18:3)PUFA/SFA
Beef 0,11
Lamb 0,15
 Can lead a reduction of cholesterol
 Desider dietary ratio 0,4
• Low cholesterol content
• Low LDL protein
• Low TG
Source :
ALA  Plant sources  reduced risk of CVD
LCn-3 Effects on heart health + platlets aggregation
+ Beneficial effects  retinal function
Beef 0,28 mg/g
Lamb 0,52 mg/g
Fish 19,9 mg/g
Lower than fish but greather consume !
Studies:
Red meat consumer «greather plasma concentration of LCn-3 PUFA than vegetarians»
 Australia 43% LCn-3 PUFA from red meat than 48% from fish.

12. • Benefit to Health
 Conjugated Linoleic Acid (CLA)
 Only ruminants dietary source  formed in the rumen
Range  in Beef 0,37-1,08 g/100g
Portugal Beef and Lamb contribute to 11% CLA intakes
CLA attention  anticancerogenic & anti- atherogenic
 they have biological good effects in humans
Cis-9 trans-11
Rumenic Acid
Other Nutrients :
 Essetial Minerals, Vitamins and Proteins
 Iron Deficency  (IDA) major nutritional deficency  vital for cellular process and
for hemoglobin
Haem Iron in meat, more BIOAVAILABLE than in Vegetables
 Vitamin Group B exceptionally B12 no present in vegetables  Methilation
Cicle
40-72 g/day  good source of Homocysteine
 Rich Sources of Zinc  < 41 mg/day – 10 mg  optimal for health
 High quaity protein and AA value

13. • Conclusion
 Moderate consumption of red meat can feeds the body with essential
nutrients
 Moderate in that case means :
 not more than 71 g/d or 500g per week
 lower amount of processed meat
 Different measurements of meat consumption in observed studies
 Red and processed meat grouped togheter  many times
 Which nutrition followed the subject group?
 no further informations like, Smoking, lifestyle, physical activity level, cooking way
and Individual genetic risk
• Weak points
NO STRONG
EVIDENCE THAT
RED MEAT IS
CAUSER OF
COLON CANCER

14.  In October, 2015, 22 scientists from ten
countries met at the International Agency for
Research on Cancer (IARC) n Lyon, France, to
evaluate the carcinogenicity of the consumption
of red meat and processed meat.
Red meat: unprocessed mammalian
muscle meat—for example, beef, veal,
pork, lamb, mutton, horse, or goat
meat including minced or frozen meat
Processed meat refers to meat
that has been transformed
through salting, curing,
fermentation, smoking, or other
processes to enhance fl avour or
improve preservation
• …6 Years later…
Carcinogenicity of consumption of red and processed
meat http://dx.doi.org/10,1016/S1470-2045(15)004444-1

15. • Avarage percentage of population that consume red meat:
1. From less than 5% to 100% for red meat, from less than 2% to 65% for
processed meat.
2. The mean intake of red is about 50–100 g to 200 g per person per day
• The Working Group assessed more than 800 epidemiological studies that investigated the
association of cancer with consumption of red meat or processed meat in many countries
• The largest body of epidemiological data  colorectal cancer:
1. In ten cohorts of European countries + some large cohorts in Sweden and Australia: 7/15
reported positive associations of colorectal cancer with high versus low consumption of red
meat.
2. Positive associations of colorectal cancer with consumption of processed meat were reported
in 12 of the 18 cohort studies that provided relevant data, including studies in Europe, Japan,
and the USA.
• …6 Years later…

16. Consumption of Red Meat
• Cancers of the pancreas, the
prostate (red meat) and stomach
(processed meat)
• Adenomas of the colorectum
• Genotoxicity and oxidative stress
• APC gene mutation or promoter
methylation (identified in 43% and
41% of colorectal samples,
respectively)
• Induces NOC formation in the
digestive tract.
Consumption of Processed red meat
• HAA
• PAH
• Bacterial Mutagenicity of human
urine
Consumption of cooked red meat
• …6 Years later…

17. ―Overall, the Working Group classified consumption of processed meat as “carcinogenic to
humans” (Group 1) on the basis of sufficient evidence for colorectal cancer. Additionally, a
positive association with the consumption of processed meat was found for stomach cancer.‖
―The Working Group classified consumption of red meat as “probably carcinogenic to
humans‖ (Group 2A).‖
―Consumption of red meat was also positively associated with pancreatic and with prostate
cancer.‖
• …6 Years later…