Low-fat diets lead to increased abnormal growths in the colon

This study was published in the Journal of Clinical Epidemiology 1994 May;47(5):525-36

 

Study title and authors:

A randomized trial of a low fat high fibre diet in the recurrence of colorectal polyps. Toronto Polyp Prevention Group.

McKeown-Eyssen GE, Bright-See E, Bruce WR, Jazmaji V, Cohen LB, Pappas SC, Saibil FG.

Department of Preventive Medicine and Biostatistics, University of Toronto, Ontario, Canada.

 

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/7730878

This study investigated the effect of a low-fat, high fibre diet on the recurrence of neoplastic colorectal polyps (abnormal growths in the colon) in patients who had had previous colorectal polyps removed. The study lasted for two years and included 201 patients who had diets of the following:
(i) Given counselling to follow a low-fat, high-fibre diet: 25% fat and 35 grams a day of fibre (lower-fat , higher-fibre group).
(ii) Told to follow a normal higher-fat, lower-fibre diet: 33% fat and 16 grams a day of fibre (higher-fat, lower-fibre group).

The study found that the lower-fat, higher-fibre group had a 20% increased risk of recurrence of abnormal growths in the colon compared to the higher-fat, lower-fibre group.

High-fibre wheat-bran is associated with a significant increase in colorectal cancer

This study was published in the New England Journal of Medicine 2000 Apr 20;342(16):1156-62

 

Study title and authors:

Lack of effect of a high-fiber cereal supplement on the recurrence of colorectal adenomas. Phoenix Colon Cancer Prevention Physicians' Network.

Alberts DS, Martínez ME, Roe DJ, Guillén-Rodríguez JM, Marshall JR, van Leeuwen JB, Reid ME, Ritenbaugh C, Vargas PA, Bhattacharyya AB, Earnest DL, Sampliner RE.

Arizona Cancer Center, Department of Medicine, University of Arizona, Tucson 85724-5024, USA. dalberts@azcc.arizona.edu

 

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/10770980

This study evaluated the effect of wheat-bran fibre in patients who had had one or more histologically confirmed colorectal adenomas removed. The study, which lasted three years, included 1,303 patients, aged 40 to 80 years, who were given wheat-bran fibre supplementation of either:
(i) 13.5 grams a day (high-fibre group).
(ii) 2 grams a day (low-fibre group).

The study found:
(a) The high-fibre group had a 5.8% increased risk of death compared to the low-fibre group.
(b) The high-fibre group had a 9.2% increased risk of any cancer compared to the low-fibre group.
(c) The high-fibre group had a 215% increased risk of colorectal cancer compared to the low-fibre group.
(d) The number of patients who reported gastrointestinal effects was significantly higher in the high-fibre group than in the low-fibre group for all effects except constipation.
Reported gastrointestinal effects:
(i) Nausea: 69% higher in the high-fibre group.
(ii) Abdominal Pain: 60% higher in the high-fibre group.
(iii) Diarrhea: 82% higher in the high-fibre group.
(iv) Constipation: 5% lower in the high-fibre group.
(v) Intestinal gas: 46% higher in the high-fibre group.
(vi) Abdominal bloating: 66% higher in the high-fibre group.

The study reveals that high-fibre wheat-bran is associated with a significant increase in colorectal cancer.

Low fat diet leads to a 150% increase in colon cancer

This study was published in the New England Journal of Medicine 2000 Apr 20;342(16):1149-55

 

Study title and authors:

Lack of effect of a low-fat, high-fiber diet on the recurrence of colorectal adenomas. Polyp Prevention Trial Study Group.

Schatzkin A, Lanza E, Corle D, Lance P, Iber F, Caan B, Shike M, Weissfeld J, Burt R, Cooper MR, Kikendall JW, Cahill J.

National Cancer Institute, Bethesda, MD, USA.

 

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/10770979

This study investigated the association between fat and fibre consumption and the development of recurrent colorectal adenomas, which are precursors of most large-bowel cancers. The study lasted for four years and included 1,905 patients who were at least 35 years old and who had had one or more confirmed colorectal adenomas removed. All patients had no history of colorectal cancer.

The patients were assigned into two groups and advised to either:
(i) Lower their fat consumption to 20% of daily calories and up their fibre consumption to 18 grams per 1000 calories. (Lower fat, higher fibre group).
(ii) Carry on with their normal diet (fat consumption of 34% and fibre consumption of 10 grams per 1000 calories). (Higher fat, lower fibre group).

The study found:
(a) Both groups had similar rates of at least one recurrent adenoma although the incidence in the lower fat, higher fibre group was .2% more than the higher fat, lower fibre group.
(b) The lower fat, higher fibre group had a 150% increased risk of developing colorectal cancer compared to the higher fat, lower fibre group.

The data from the study shows that patients with colorectal adenomas have an increased risk of developing colorectal cancer if they follow a low fat, high fibre diet.

High-fibre supplement (psyllium) linked to colon cancer risk

This study was published in the Lancet 2000 Oct 14;356(9238):1300-6

 

Study title and authors:

Calcium and fibre supplementation in prevention of colorectal adenoma recurrence: a randomised intervention trial. European Cancer Prevention Organisation Study Group.

Bonithon-Kopp C, Kronborg O, Giacosa A, Räth U, Faivre J.

Registre Bourguignon des Tumeurs Digestives, Faculté de Médecine de Dijon, France.

 

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/11073017

Ispaghula husk is a soluble fibre that comes from a shrub-like herb, Plantago psyllium. Ispaghula husk is also known as psyllium, psyllium seed, psyllium husk, ispaghula or ispaghula seed.

Ispaghula husk is a central ingredient in many high-fibre cereals, and is often combined with wheat and oats. It is also contained in many processed foods such as "health drinks", bread, biscuits, rice cakes, instant noodles and other bakery products and is also sold as a supplement such as Metamucil, Colon Cleanse, Serutan, Fybogel, Bonvit, Effersyllium, and Konsyl. 

This study investigated the effect of ispaghula husk supplementation on recurrence of colorectal adenomas in patients with a history of colorectal adenomas. (An adenoma is a benign tumor of glandular origin. Although these growths are benign, over time they may progress to become malignant). The study included 665 patients who received either supplementation or placebo and were followed for three years.

The study found that patients who had the ispaghula husk had a 67% increased risk of recurrence of colorectal adenomas compared to patients who had placebo.