Nutrition and Cancer

1
Nutrition and Cancer
Lecture 21April 10, 2008Dr. QuadroFood
Science Department
2
The leading causes of death in the United States
3
Cancer

• Cancer is the 2nd leading cause of death in the
  US (after heart disease).
• 1 out of 4 Americans dies of cancer.
• The risk of developing cancer can be reduced by
  changes in lifestyle.

4
What is cancer?

• Cancer is the uncontrolled growth and spread of
  abnormal cells (cells do not die!).
• Cancer is the generic name for different
  diseases, usually classified according to the
  part of the body where it is first found.

5
Cell Theory

• 1) Every organism is composed of one or more
  cells.
• 2) A cell is smallest unit having the properties
  of life.
• 3) Continuity of life arises from growth and
  division of single cells.

6
Cell

• Smallest unit of life.
• Can survive on its own or has potential to do so.
• Is highly organized for metabolism.
• Senses and responds to environment.
• Has potential to reproduce.

7
Structure of Cells

• Plasma membrane
• Cytoplasm
• Nucleus (compartment where DNA is stored)

8
What does a cell do?
9
Cell Cycle
10
What is cancer?

• Abnormal cell cycle regulation
• Not a single disease
• Many causes, Different details

11
What is cancer?

• Cell proliferation
• cells division is out of control (cells
  divide too fast and/or at the wrong time/place)
• Apoptosis (programmed cell death)
• the self-destruct sequence of old or damaged
  cells fails

12
What is cancer?
13
Intestinal epithelium
Normal
Abnormal
14
Types of Cancer

• Sarcoma-from connective tissues (muscle or bone).
  More common in younger people.
• Carcinomas-epithelial tissues (lung, breast,
  prostate, and colon). More common in older
  people.

15
Types of Cancer

• Leukemia-cancers of the blood or blood forming
  organs (bone marrow).
• Lymphomas- affect the lymphatic system. The
  lymphatic system is a group of vessels and nodes
  that act as the bodys filter. It prevents
  bacteria and foreign invaders from entering the
  bloodstream.

16
Causes of Cancer

• 80 are considered sporadic (not hereditary)
• Different types of cancer have different risk
  factors
• There are several risk factors
• Age- risk increases 50
• Diet- high fat, high cholesterol diets

17
Causes of Cancer

• Several risk factors (continue)
• Obesity- no clear reasons/link
• Cigarettes- increases lung cancer. Other tobacco
  products such as pipes and chewing tobacco,
  increase risk of mouth cancer.
• Long term exposure to chemicals- asbestos, radon
  and benzene.

18
Causes of Cancer

• Several risk factors (continue)
• Exposure to high levels of radiation
• Harmful ultraviolet rays from the sun
• Some viruses- Hepatitis B, C, Human Papilloma
  Virus (HPV), Epstein-Barr (mononucleosis)
• Immune system diseases

19
Causes of Cancer

• Hereditary
• Screenings are recommended for high risk
  families. One is considered at high risk if
  several relatives have had cancer or if someone
  in the family had cancer at a very early age.

20
Carcinogenesis
21
Carcinogenesis
22
Carcinogenesis
23
Diet and cancer

• Dietary factors act as
• -Initiators
• Promoters
• Antipromoters

24
Elevated serum vitamin D levels may help
curb development and progression of breast cancer
25
Where is the Colon ?
Colorectal cancer
26
What does the colon do?

• Stores mainly non-absorbed food, fiber and water
• Re-absorbs nearly all water
• Moves solid waste to the rectum where it is
  eliminated by defecation

27
How does colorectal cancer develop?

• It begins as polyps (tiny abnormal growths on the
  inside walls of the colon or rectum).
• Polyps vary in size, from less than a millimiter
  to a few centimeters.
• Some polyps become cancerous after several years
  and should be removed to prevent development of
  colorectal cancer.

28
X-Ray of Colon and Polyps
29
Why the Concern?

• Leading cause of cancer-related death
• 4th-worldwide
• 2nd- United States
• Why the difference between world and US ?

30
What factors increase risk of developing
colorectal cancer?

• Poor Diet
• high fat
• high content of red meat
• high temperature cooking of red meats (polycyclic
  aromatic hydrocarbon)
• low vegetables consumption
• high alcohol consumption
• low water consumption

31
What factors increase risk of developing
colorectal cancer?

• Physical inactivity

32
Why the Difference Between World and U.S. Rates?

• Colorectal Cancer has been called a Cancer of
  Economically Developed Countries
• Diet is different
• Physical activity is different

33
Ways to Reduce Your Risk

• Regular moderate exercise
• Eat healthy diet
• Maintain proper weight
• Avoid smoking
• Limit alcohol use
• GET REGULAR SCREENING

34
Ways to Reduce Your RiskHealthy
DietFive-A-Day is ? 5 servings of fruits
vegetables / dayThis can reduce your risk for a
number of diseases, not only colorectal cancer
35
Ways to Reduce Your Risk

• Physical activity recommendations
• For 30 minutes
• At least 5 times per week
• At the pace of brisk walking

36
Ways to Reduce Your Risk
Most important weapon in fight against cancer
SCREENING

• Prevention
• Finding polyps in the colon and removing them
  before they become cancerous
• Early detection
• Treatments are most affective when cancer is
  found early

37
Screening tests

• Fecal Occult Blood Test (FOBT)
• Flexible Sigmoidoscopy
• Colonoscopy
• Double Contrast Barium Enema

38
Who should be screened for colorectal cancer?

• EVERYONE aged 50 and older
• Women and men
• All races and ethnicities
• YOUNGER than 50 for those with a family history
  of colorectal cancer or colorectal polyps

39
Who Is At Risk of Developing Colorectal Cancer?

• Men AND Women are at similar risk
• Risk increases with age (? 90 occurs in people
  aged 50)
• 85 of people with colorectal cancer had NO
  medical history related to colorectal cancer.

40
(No Transcript)
41
AICRAmerican Institute for Cancer Research

• www.aicr.org