Dietary fat and risk of breast cancer

Dietary fats: Know which types to choose

Certain Fats Help Develop Cancer Regardless of Obesity

Types of dietary fat and cancer

[GOOGLEFREETEXTUNIQ-5-7arthritis and chronic alcoholism]

Breast cancer is one of the major public health problems among women worldwide. A number of epidemiological studies have been carried out to find the role of dietary fat and the risk of breast cancer. The main objective of the present communication is to summarize the evidence from various case-control and cohort studies on the consumption of fat and its subtypes and their effect on the development of breast cancer, types of dietary fat and cancer.

A Pubmed search for literature on the consumption of dietary fat and risk of breast cancer published from January through December was carried out. Increased consumption of total fat and saturated fat were found to be positively associated with the development of breast cancer. Even though an equivocal association was observed for the consumption of total monounsaturated fatty acids MUFA and the risk of breast cancer, there exists an inverse association in the case of oleic acid, the most abundant MUFA.

A moderate inverse association between consumption of n-3 fatty acids and breast cancer risk and a moderate tiotropium and cardiovascular association between n-6 fatty acids and breast cancer risk were observed.

Even though all epidemiological studies do not provide a strong positive association between the consumption of certain types of dietary fat and breast cancer risk, at least a moderate association does seem to exist and this has a number of implications in view of the fact that breast cancer is an increasing public health concern. It is estimated that more than 1. Incidence rates of breast cancer are approximately 90 perwomen in developed countries and those in developing countries are approximately ten to sixty perwomen [ 1 ].

Several studies types of dietary fat and cancer been carried out to identify the risk factors for developing breast cancer. Studies of reproductive factors suggest that nulliparity and late age at first childbirth are the most consistent risk factors associated with breast cancer [ 2 ].

Certain dietary factors such as a higher intake of fat and meat also seem to increase the risk of breast cancer [ 34 ]. Fat is a macronutrient and is considered to be a major source of calories or energy. Although some fat in the diet is necessary, too much of fat can lead to heart diseases, cancers, types of dietary fat and cancer, obesity and other health problems. Numerous studies in women, using different study designs and in different geographical areas have been carried out in order to establish the relationship of dietary fat to breast cancer risk.

The objective of the present communication is to summarize evidence from various case-control and cohort studies on the consumption of dietary fat and its sub-types [saturated, monounsaturated MUFA and polyunsaturated PUFA fatty acids] types of dietary fat and cancer their effect on the development of breast cancer.

The major sources of saturated fats are meat, poultry, dairy products, types of dietary fat and cancer, eggs and some plant foods such as coconut, coconut oil and palm oil [ 5 ]. High concentrations of MUFA are found in vegetable oils and their traces are also found in meat. Oleic acid, the most abundant MUFA, is found in animal and vegetable oils. Oleic acid is the major component of olive oil. PUFAs are mostly found in plants, types of dietary fat and cancer, fish and seafoods.

Rich sources of n-3 PUFA include mackerel, salmon, and albacore tuna [ 6 ]. Types of n-3 fatty acids include eicosapentaenoic acid EPA; N-6 fatty acids are found in high concentration in corn oil, safflower oil, soybean oil, sunflower oil and cottonseed oil. Types of n-6 fatty acids include linoleic acid A Pubmed search of the literature was carried out covering studies conducted over a period of fourteen years from to using keywords " dietary fat" and "risk" and "breast cancer".

Only case-control and cohort studies conducted among women were considered for the present review. Of the seventeen case-control studies [ 69 - 24 ] that investigated the relation of total dietary fat with risk of breast cancer, seven studies reported a significant positive association between total fat intake and risk of breast cancer [ 101117 - uterine cancer and the pill2224 ].

The odds ratios OR of these studies ranged from 1. Significant dose-response relationships between the increased consumption of total fat and breast cancer risk were observed in four studies [ 11182224 ]. Non-significant increased risks were reported in six studies [ 61416202123 ]. Significant reduced risk with a dose-response relationship was observed in one study [ 12 ].

Three studies have shown no association [ 91315 ] Additional file 1. Of the twenty cohort studies, which investigated the relationship between total dietary fat intake and breast cancer risk, ten were based exclusively on post-menopausal women [ 25 - 34 ].

Five studies showed significant positive associations with dose-response relationships between total fat types of dietary fat and cancer breast cancer risk [ 2526313435 ].

The relative risks for these studies ranged from 1. Non-significant positive associations between total fat and the risk of breast cancer were observed in nine studies [ 30323336 - 41 ].

Six studies found no association between the fat intake and the risk of breast cancer [ 27 - 2942 - 44 ] Additional file 2. Four studies out of the seventeen reviewed here found significant positive associations with dose-response relationships between saturated fat and breast cancer [ 9181945 ].

The odds ratios for these studies ranged from 1, types of dietary fat and cancer. Nine studies showed non-significant increase in associations of saturated fat with the development of breast cancer [ 121416212346 - 4866 ]. Four studies reported no association between saturated fat and breast cancer risk [ 6154950 ] Additional file 1. Among the seventeen cohort studies, three reported positive associations with significant dose-response relationships between the consumption of saturated fat and the risk of breast cancer [ 263641 ].

Non-significant increased associations for breast cancer were found in eight studies [ 30 - 3337384051 ]. Six studies found no associations between the consumption of saturated fat and the risk of breast cancer [ 272834424352 ] Additional file 2.

Two studies of increased consumption of oleic acid the most abundant MUFA [ 1257 ] and four studies of increased consumption of olive oil a major component of oleic acid [ 4854 - 56 ] reported reduced risks of breast cancer.

No association was observed in one study for the consumption of oleic acid [ 53 ] Additional file 1. Some cohort studies found that increased consumption of oleic acid reduced the risk of breast cancer but the associations were non-significant [ 323343 ]. However, other studies have shown no association [ 2740 ] Additional file 2. Contrary to the studies on oleic acid consumption, three of the twelve case-control studies reported positive associations with a dose-response relationship between increased consumption of total MUFA and the risk of breast cancer [ 1618types of dietary fat and cancer ].

Non-significant increased associations for higher consumption of MUFA were found in three studies [ 62123 ]. The rest of the studies reviewed reported no association between MUFA consumption and subsequent risk of breast cancer [ 14154648 - 50 ] Additional file 1.

Of the twelve studies that have been reviewed, three showed significant positive associations with dose-response relationships for increased intake of MUFA and the risk of breast cancer [ 343738 ]. Five studies reported non-significant increased breast cancer risk [ 2830313651 ]. Three studies showed inverse associations with significant dose-response relationships between the higher intake of MUFA and the risk of breast cancer [ 334252 ].

The relative risks of these studies varied from 0. No significant association between the consumption of MUFA and breast cancer was found in one study [ 41 ] Additional file 2.

Six studies out of fourteen reported a significantly reduced breast cancer risk with increased PUFA consumption [ 121545types of dietary fat and cancer, 485766 ]. The odds ratios for these studies ranged from 0. Decreased breast cancer risk with significant dose response patterns was reported for high consumption of PUFA in three studies [ 121557 ]. No associations were found between PUFA intake and risk of breast cancer in eight studies [ 614161821234649 ] Additional file 1.

Contrary to the results based on case-control studies, types of dietary fat and cancer, three out of eleven cohort studies reported significant positive associations with dose-response relationship between the increased consumption of PUFA and the risk of breast cancer [ 303452 ]. The relative risks of these studies ranged from 1. Four studies reported non-significant increased risks associated with increased PUFA consumption [ 28313638 ]. Nanoparticle silver antibacterial plastic containers studies reported no association between the consumption of PUFA and risk clean smoth antibacterial breast cancer [ 33414251 ] Additional file 2.

One study of n-3 fatty acids [ 58 ] and another study of DHA reported significantly reduced risks for breast cancer [ 59 ] Additional file 1. A significantly reduced breast cancer risk with a dose-response relationship was observed in one study for the increased consumption of DHA n-3 fatty acid [ 59 ].

Two studies of consumption of alpha-linolenic acid showed inverse association with a significant dose-response relationship [ 5059 ]. One study of EPA n-3 fatty acid showed an inverse association [ 58 ]. No association was observed in other studies for the increased consumption of n-3 fatty acids [ 6165355 ] with the development of breast cancer Additional file 1. Contrary to the above result, a Swedish cohort study among post-menopausal women reported a significantly increased breast cancer risk with dose-response relationship [ 34 ].

The other studies showed no associations types of dietary fat and cancer breast cancer incidence on the consumption of n-3 fatty acids [ 3651 ], DHA [ 33 ] and EPA [ 3351 ] Additional file 2.

Two studies of n-6 fatty acids reported non-significant increased breast cancer risks [ 5558 ]. No associations were observed for the consumption of n-6 fatty acids [ 505359 ] with the development of breast cancer Additional file 1.

Non-significant increased breast cancer risks were observed with increased consumption of n-6 fatty acids [ 28 ] and linoleic acid n-6 fatty acid [ 3133 ]. A few studies found no risk of breast cancer with the consumption of linoleic acid [ 27324043 ] and arachidonic acid n-6 fatty acid [ 33 ] Additional file 2.

Types of dietary fat and cancer of the case-control studies discussed here have shown increased breast types of dietary fat and cancer risk with increased total fat consumption, types of dietary fat and cancer.

However, results of cohort studies did not offer the same degree of consistent support. Case-control and cohort studies share some strengths and limitations. The primary advantages are the ability to measure diet and potential confounding types of dietary fat and cancer relatively accurately and uniformly at the individual level in both the types of study designs.

Also, the subjects in most of the studies were generally drawn from a relatively uniform population. Despite these advantages, there remains a number of limitations common to both case-control and cohort studies.

As fat intake is estimated by food frequency questionnaire FFQ in most of the studies discussed in the present vitamin c and ala cancer cure, there remains a certain amount of measurement error in such procedures.

Non-differential random measurement error i. Only a few studies mentioned about validated FFQ [ 6142428335366 ]. Non-validated questionnaire for collecting the dietary information might also affect the reliability of study results.

Another important limitation identified by the present review is that most of the studies are generally conducted in a relatively homogenous population; hence anger at cancer patient range of fat intake and the power of the study to detect a true association is restricted.

Due to the lack of a definitive biologic mechanism and the lack of information on the relevant timing of exposure, it is possible that case-control and cohort studies are measuring diet at the wrong point in time; this again might attenuate the observed risk in any particular study. The main contrast between case-control and cohort studies lies in their differing potential for bias and in the resources required. Selection bias would occur if participation in a case-control study was correlated with fat intake and if cases and controls have different participation rates.

In many of the case-control studies discussed here, types of dietary fat and cancer, particularly those conducted in highly industrialized populations such as the United States, there is often a substantial refusal to participate, particularly among control subjects, and it is possible that there is preferential participation by health-conscious individuals, who might have a relatively low fat intake.

Such a phenomenon might introduce an artificial positive association between fat intake and breast cancer risk. Recall bias might occur since cases are interviewed after diagnosis and might report their past diet differently to control subjects. In particular, they could report their diets more accurately through better motivation, or conversely, they could report an over inflated fat consumption if aware of the postulated association between fat intake and breast cancer risk.

Since there are many limitations associated with case-control studies, the results from the cohort studies can be considered more authentic.

These valtrex and oral herpes and dosage normally considered free of the most common biases that potentially affect case-control studies such as selection and information bias. Even though most of the cohort studies failed to find an association between total dietary fat intake and breast cancer risk, some studies reported a significant positive association with dose-response relationship [ 25types of dietary fat and cancer, 26313435 ].

The failure of cohort studies to show a consistent and a strong relationship may be attributed to the difficulty in collecting accurate dietary information.

 

Types of dietary fat and cancer

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