As per WHO, Cancer is the second leading cause of death globally and is estimated to account for 9.6 million death in 2018. Between 30% and 50% of cancer deaths could be prevented by modifying or avoiding key risk factors by improving diet, reducing tobacco use, maintenance of healthy body weight, limiting alcohol consumption and cessation of smoking. At least 35% of all cancers worldwide are caused by an incorrect diet, and in the case of colon cancer, diet may account for 80% of the cases. Recently emphasis has been put specifically to explore the chemo-protective role of diet.
1. Control your Calorie Intake
Regularly stuffing yourself with the excess food plays a pivotal role as a risk factor for cancer. Excess calories aggravate the risk of obesity, an additional risk factor of many malignancies:
- Breast (postmenopausal women)
- Colon and rectum
- Endometrium (lining of the uterus)
Oesophagus or food pipe
Being overweight or obese also likely raises the risk of other cancers:
- Non-Hodgkin lymphoma
- Multiple myelomas
- Aggressive forms of prostate cancer
Too much belly fat is linked with an increased risk of colorectal cancer and is probably linked to a higher risk of cancers of the pancreas, endometrium (lining of the uterus), and breast cancer (in women past menopause).
How can you Lower the Number of Calories?
It does not mean that one should starve himself. Restrict your calorie intake without depriving yourself of essential vitamins, minerals and other vital nutrients. The basic idea is to eat a reduced amount of food (about 70–80 per cent of the amount required to maintain “normal” body weight).
- Eating smaller amounts of food (lowering portion sizes),
- Limiting between-meal snacks,
- Limit foods and drinks that are high in calories, fat, and/or added sugars, and that provide few nutrients.
- Avoid highly refined and processed food, junk food, Fried foods, cookies, cakes, candy, ice cream, and regular soft drinks
- Replace your unhealthy food habits with vegetables and fruits, whole grains, beans, and lower calorie beverages.
2. Glucose Metabolism
Elevated fasting glucose and fasting insulin, 2-hour levels of glucose and insulin after an oral glucose challenge, and larger waist circumference were associated with a higher risk of colorectal cancer. Sedentary lifestyle and overweight further worsen the situation.
Foods which contribute to hyperinsulinemia, such as refined sugar, foods containing refined sugar, and refined flour products should be avoided and eliminated from a cancer-protective diet.
The glycemic index is an indication of the blood sugar response of the body to a standardized amount of carbohydrate in a food. Diet with High glycemic load have a risk of following cancer:
– Upper aerodigestive tract
– Endometrium of uterus and Ovaries
– Colon or colorectal cancers.
Diabetes also has been linked to an increased risk of colorectal cancer, endometrial cancer, and pancreatic cancer.
3. Low Fiber – Increase Intake
Fibre is the carbohydrate in plant foods. The human body is not designed to digest fibre. About 30 grams of fibre each day is a good minimum goal. That’s at least 5 servings of vegetables and fruit plus at least three small servings of whole grains.
The fibre in the diet also:
- slows digestion, so you feel full longer
- increases the bulk and weight of stool, diluting harmful substances and speeding their elimination from the body
- protects the lining of the colon
- helps control body weight
There are two types:
1. Soluble fibre dissolves in water.
- Various other fruits and vegetables
2. Insoluble fibre does not dissolve in water
- Dark leafy greens
- Whole-wheat foods
- Legumes (dried beans, peas, lentils)
- Many other fruits and vegetable
Plant foods rich in dietary fibre help protect us against cancer of the mouth, pharynx, larynx, oesophagus, colon, rectum and stomach.
Some soluble fibres also help lower blood sugar, may aid in insulin sensitivity and help lower blood cholesterol.
Unrefined plant foods typically have an abundance of fibre. Food processing refines the final product (refined grains) generally lacking in fibre. Animal origin products -milk or dairy products, eggs, and meat all have this in common – they contain no fibre. Refined grain products also have most of the dietary fibre removed from them. So, a diet high in animal products and refined grains are low in fibre.
4. Red Meat and Processed Meats
Red meat is defined as any meat that has more of the myoglobin (muscle protein) than “white meat”.
Red meat refers to all mammalian muscle meat, including, beef, veal, pork, lamb, mutton, horse, and goat.
Processed meat refers to meat that has been transformed through salting, curing, fermentation, smoking, or other processes to enhance flavour or improve preservation. Example: hot dogs (frankfurters), ham, sausages, corned beef, and biltong or beef jerky as well as
Red meat consumption has been linked to diabetes, stroke, cancer (colon and rectum), morbidity and mortality. The evidence that red meat causes cancer is not as strong as processed meat.
Generally meets are cooked at high temperatures, which may form Mutagenic heterocyclic amines and polycyclic aromatic hydrocarbons. Processed meat may contain nitrites and their related compounds which may be converted to carcinogenic N-nitroso
compounds in the colon.
5. Omega 3:6 Ratio Imbalance
Long-chain n-3 and n-6 PUFAs are synthesized from the essential fats (EFAs) alpha-linolenic acid (ALA) and linoleic acid, respectively.
Omega 3 fats (alpha-linolenic acid, EPA, DHA) have been shown in animal studies to be protected from cancer, while omega 6 fats (linoleic acid, arachidonic acid) have been found to be cancer promoting. A higher ratio of N-3 to N-6 fats in the diet has been to reduce the risk of breast cancer.
Flaxseed oil and DHA (from an algae source) both can be used to increase the intake of N-3 fat, with DHA being a more efficient, sure source.
Flaxseed is an excellent source of dietary fibre, omega 3 fat (as alpha-linolenic acid), and lignans (main anticancer component). The lignans in flaxseed are metabolized in the digestive tract to enterodiol and enterolactone, which have estrogenic activity. Also, Flax seed is a more potent source of phytoestrogens than soy products.
7. Fruits and Vegetables
As per the joint report of World Cancer Research Fund and the American Institute for Cancer Research, a diet rich in fruit and vegetable would reduce cancers of the mouth and pharynx, oesophagus, lung, stomach, and colon and rectum; probable risk reduction of cancers of the larynx, pancreas, breast, and bladder.
Possible protective elements in fruits and vegetables: dithiolthiones, isothiocyanates, indole-32-carbinol, allium compounds, isoflavones, protease inhibitors, saponins, phytosterols, inositol hexaphosphate, vitamin C, D-limonene, lutein, folic acid, beta carotene (and other carotenoids), lycopene, selenium, vitamin E, flavonoids, and dietary fibre.
Allium vegetables, carrots, green vegetables, cruciferous vegetables, and tomatoes also had a fairly consistent protective effect.
Cruciferous vegetables (broccoli, cauliflower, cabbage, Brussels sprouts) contain sulforaphane, which has anti-cancer properties.
Allium vegetables (garlic, onion, leeks, chives, scallions, and shallots) are rich in flavonols and organosulfur compounds, which have tumour-inhibitory properties and found to be protective for stomach and colorectal cancers and prostate cancer.
Selenium is a mineral with anti-cancer properties. Selenium encourages cancerous cells to under degradation. Selenium can decrease the rate of tumour growth.
Poor selenium levels, especially for men, are a cancer risk. If a person has low selenium levels and other antioxidant defences are also low the cancer risk is increased even further. Higher levels of selenium also provide protection against colon cancer and lung cancer.
Good vegetarian sources of selenium are whole grains and legumes grown in selenium-rich soil, brazil nuts (by far the densest source of selenium), nutritional yeast, brewers yeast, and sunflower seeds.
9. Protective Vitamins
Vitamin B-12 is an important nutrient for genetic stability, DNA repair, carcinogenesis, and cancer therapy.
Folic acid plays a crucial role in DNA synthesis. Dark green leafy vegetables are a rich source of folic acid.
Higher intakes of folic acid and their related nutrients (vitamin B-6 and B-12). have found to reduce the incidence of colon, rectal, and breast cancer.
Alcohol is an antagonist of folate, so that drinking alcoholic beverages greatly magnifies the cancer risk of a low-folate diet.
Vitamin D is a fat subtle vitamin present in the human body which is primarily formed from the exposure of the skin to sunshine.
10. Antioxidants, “Free Radical Scavengers”
Antioxidants are required in the body to combat free radical injury which may be produced in the body as a part of the normal physiological process. Free radicals are highly stable and reactive. Antioxidants can be endogenous, formed in the body. However, body chiefly has to rely on the external source of antioxidant (exogenous antioxidants). These exogenous antioxidants are commonly called dietary antioxidants. Fruits, vegetables, and grains are rich sources of dietary antioxidants. Some dietary antioxidants are also available as dietary supplements.
α- and β-Carotene and Other Carotenoids
Dietary carotenoids are cancer preventative. Alpha-carotene is a more potent agent than β-carotene. The richest source of α-carotene is carrots and carrot juice, with pumpkins and winter squash as a second most-dense source.
Lycopene has been found to be very protective, particularly for prostate cancer. The major dietary source of lycopene is tomatoes, with the lycopene in cooked tomatoes being more bioavailable than that in raw tomatoes.
Vitamin C is a water-soluble antioxidant. Vitamin C is correlated with overall good health and cancer prevention. At the high concentrations, ascorbate is preferentially toxic to cancer cells.
Probiotics are bacteria living in a symbiotic relationship with their host. Probiotics bacteria produce natural antibiotics to keep pathogenic bugs in check and produce some B vitamins in the small intestine where they can be utilized. Beneficial bacteria help strengthen the immune system and prevent food allergies. Probiotics can help prevent cancer at various stages of development. These good bacteria can improve mineral absorption, maximizing food utilization.
A. Lactobacillus species and Eubacterium aerofaciens, both producers of lactic acid, were associated with the populations with the lower risk of colon cancer, while. Bacteroides anodes indium species were associated with a higher risk of colon cancer. Probiotic bacteria reduce the level of procarcinogenic enzymes such as beta-glucuronidase, nitroreductase, and azoreductase.
14. Oral Enzymes
Very often, people diagnosed with cancer have a problem with the digestion or gut related issues. Moreover, impairment with digestion will hinder a nutritional approach to treat cancer. No matter how nutritious food you consume, it is worthless if your digestion is not adequate.
Enzymes, especially proteases, if they reach systemic circulation, can have direct antitumour activity.
In nutshell Anticancer diet should have:
• Adequate, but not excessive calories,
• 10 or more servings of vegetables a day, including cruciferous and allium vegetables; vegetable juice couantietumour activity goal,
• 4 or more servings of fruits a day,
• high in fibre no refined sugar,
• no refined flour,
• low in total fat, but containing necessary essential fatty acids,
• no red meat,
• a balanced ratio of omega 3 and omega 6 fats and would include DHA,
• flax seed as a source of phytoestrogens,
• supplemented with ~200 μg/day selenium,
• supplemented with 1,000 μg/day methylcobalamin (B-12),
• very rich in folic acid (from dark green vegetables),
• adequate sunshine to get vitamin D, or use 1,000 IU/day supplement,
• very rich in antioxidants and phytochemicals from fruits and vegetables, including α-carotene, β-carotene, β-cryptoxanthin, vitamin C (from foods), vitamin E (from foods),
• very rich in chlorofibre,
• supplemented with beneficial probiotics,
• supplemented with oral enzymes
I am providing a link of IARC, International agency for research on Cancer (WHO) here, you can retrieve information of Cancer statistics of any area and in any country.