Are polyunsaturated fats healthy?

This post includes a synopsis of a study published in Cholesterol-And-Health.Com Special Reports Volume 1 Issue 2 and a recipe for simple beef brisket.

Study title and author:
How Essential Are the Essential Fatty Acids? The PUFA Report Part 1: A Critical Review of the Requirement for Polyunsaturated Fatty Acids
By Chris Masterjohn.

This paper can be accessed at: http://www.cholesterol-and-health.com/PUFA-Special-Report.html

In this review Masterjohn notes that current reviews and textbooks call the omega-6 linoleic acid and the omega-3 alpha-linolenic acid "essential fatty acids" (EFA) and cite the EFA requirement as one to four percent of calories.
                                                                                                                                            Books:

Research suggests, however, that:

(a) The omega-6 arachidonic acid (AA) and the omega-3 docosahexaenoic acid (DHA) are the only fatty acids that are truly essential. Eicosapentaenoic acid (EPA) occurs in fish products but is probably not a normal constituent of the mammalian body and in excess it interferes with essential AA metabolism.
(b) The EFA requirement cited in the scientific literature is inflated by several factors: the use of diets composed mostly of sucrose, glucose, or corn syrup; the use of diets deficient in vitamin B6; the use of purified fatty acids instead of whole foods; the use of questionable biochemical markers rather than verifiable symptoms as an index for EFA deficiency; and the generalization from studies using young, growing animals to adults.
(c) The true requirement for EFA during growth and development is less than 0.5 percent of calories when supplied by most animal fats and less than 0.12 percent of calories when supplied by liver. On diets low in heated vegetable oils and sugar and rich in essential minerals, biotin, and vitamin B6, the requirement is likely to be much lower than this. Adults recovering from injury, suffering from degenerative diseases involving oxidative stress, or seeking to build muscle mass mass may have a similar requirement.
(d) For women who are seeking to conceive, pregnant, or lactating, the EFA requirement may be as high as one percent of calories. In other healthy adults, however, the requirement is infinitesimal if it exists at all.
(e) The best sources of EFAs are liver, butter, and egg yolks, especially from animals raised on pasture.
(f)  During pregnancy, lactation, and childhood, small amounts of cod liver oil may be useful to provide extra DHA, but otherwise this supplement should be used only when needed to obtain fat-soluble vitamins.
(g) Vegetarians or others who eat a diet low in animal fat should consider symptoms such as scaly skin, hair loss or infertility to be signs of EFA deficiency and add B6 or animal fats to their diets.
(h) An excess of linoleate from vegetable oil will interfere with the production of DHA while an excess of EPA from fish oil will interfere with the production and utilization of AA.
(i) EFA are polyunsaturated fatty acids (PUFA) that contribute to oxidative stress (cell, tissue, or organ damage). Vitamin E and other antioxidant nutrients cannot fully protect against oxidative stress induced by dietary PUFA. Therefore, the consumption of EFA should be kept as close to the minimum requirement as is practical while still maintaining an appetizing and nutritious diet.

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Recipe of the day

Simple Beef Brisket

Ingredients                                                                                                          Food Mall: Beef Brisket

1 4-5 lb brisket

2T olive oil
4 leeks, white, light green parts sliced thinly
4 carrots, sliced
18 cloves garlic
1 C dry red wine
1 T tomato puree
2 bay leaves, crumbled
1 1/2 T dry thyme
fresh chopped cilantro for garnish

Directions:
Preheat oven to 325.

Dry brisket. Season with salt, pepper. Heat oil in heavy roasting pan. Brown brisket.

Sprinkle leeks, bay leaves, garlic, carrots on bottom of pan and on top of brisket. Add wine, tomato paste, thyme. Bring to boil with meat. Season with sea salt, freshly ground pepper.

Cover, bake 2 1/2-3/12 hrs or till fork tender. Chill, slice.

May be made 3 days ahead. When ready to serve, reduce sauce, taste, adjust seasoning. Reheat at 350 30 min before serving.

Women who eat less saturated fat have a smaller chance of becoming pregnant

This post includes a summary of a paper published in Fertility and Sterility 1990 Oct;54(4):632-7

Study title and authors:
High dietary fiber and low saturated fat intake among oligomenorrheic undergraduates.

Snow RC, Schneider JL, Barbieri RL.

Department of Population Sciences, Harvard School of Public Health, Boston, Massachusetts 02115.

This paper can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/2170167?dopt=Abstract

Oligomenorrhea is infrequent or light menstruation, with only four to nine periods in a year. Because they are ovulating less women with oligomenorrhea  have a smaller chance of becoming pregnant.

This study evaluated the nutrient intake, in 35 eumenorrheic (normal menstruation), 11 mildly oligomenorrheic, and 10 oligomenorrheic nonathletic undergraduate women.

Oligomenorrheic women were found to consume significantly more dietary fiber, crude fiber, and polyunsaturated fat, and significantly less saturated fat than women with normal menstruation.

Snow concluded: "The data suggest that higher intake of fiber and lower intake of saturated fat may be associated with oligomenorrhea among otherwise healthy undergraduate nonathletic women".