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You will have to take responsibility for doing your own research, and making your own decisions. Fat as an Essential Nutrient The human body needs three types of macronutrients: fat, protein, and carbohydrates. (The essential vitamins and minerals are called micronutrients, since they are needed in much lesser quantity.) Of these three essential macronutrients, fat is perhaps the hardest to obtain from the home garden. Many commonly-grown garden plants are good sources of carbohydrates, such as tomatoes, peppers, onions, potatoes, watermelon, corn, etc. And a number of good plant sources of protein can be grown in a small garden, such as beans, peas, and (with some effort) various grains. But the vast majority of these garden-grown food sources are low in fat. On many grocery store shelves, and in many advertisements for foods, consumers will find the boast that a particular food is low in fat. Many processed foods are designed to be low in fat. And this effort to reduce the fats in food is not without a basis in health concerns, since the typical Western diet has an excessive percentage of fat. However, fat is an essential nutrient. And if you were to obtain most of your nutrition from a large garden, obtaining enough essential fatty acids for a healthy diet would require some extra thought and effort. Edible fats have a long fatty chain (consisting entirely of carbon and hydrogen atoms) at one end, and an acid group at the other end (hence the name, fatty acids). The acid group is the last carbon in the chain which is bonded to an oxygen molecule by a double bond, and then to an OH group (oxygen-hydrogen) by a single bond. The bonds between the carbon atoms in the long fatty chain can be double or single, and the total number of carbon atoms in the chain can vary, which accounts for the different types of fatty acids. If there are no double bonds between the carbon atoms in the fatty chain, the fat is called saturated (because it has as many hydrogen atoms as is possible for that length of carbon atoms). If there is one double bond, the fat is called mono-unsaturated. If there are two or more double bonds, the fat is called poly-unsaturated. If the fat has 18 carbon atoms, 3 double bonds, and the first double bond begins with the third carbon [w3] (starting at the end furthest from the acid group), then the fat is written as 18:3w3 (or 18:3n3). This particular poly-unsaturated fatty acid is called alpha-linolenic acid, and it is the most common plant source of omega-3 fatty acids. There are a number of other possible configurations of fatty acids which would have an omega-3 (w3) in its designation. These fatty acids are all called omega-3 fatty acids. Omega-3 fatty acids are one of only two types of fatty acids which are essential in the human diet. The other essential type of fat is called omega-6 fatty acid. These have the first double bond beginning with the sixth carbon atom. An example of an omega-6 fatty acid would be the poly-unsaturated 18:2w6 fatty acid (18 carbon atoms; 2 double bonds, the first beginning on the sixth carbon atom, w6), which is called linoleic acid. It is the most common plant source of omega-6 fatty acids. Omega-3 and omega-6 fatty acids are the essential fatty acids. The human body cannot survive and maintain health within normal limits without both these types of fat. Other types of fat are useful to health, but non-essential. For example the omega-9 fatty acid 18:1w9 (18 carbon atoms; 1 double bond beginning on the ninth carbon atom, w9), the main component of olive oil, is healthy but not essential. An example of a saturated fat would be 18:0 (18 carbon atoms; zero double bonds). Although there are many different types of fatty acids, only two types are essential in the human diet: omega-3 and omega-6 fatty acids. The other types of fat can be manufactured by the body from these two essential fatty acids, and from carbohydrates. A diet that is deficient in either omega-3 or omega-6 fatty acids is unhealthy in the short term, and more harmful as time passes. The most common plant source of omega-6 fatty acid is linoleic acid (18:2w6), which is abbreviated LA. The most common plant source of omega-3 fatty acid is alpha-linolenic acid (18:3w3), which is abbreviated LNA (or ALA) How Much Fat Is Enough? The U.S. DRV (daily recommended value) for fat intake is 30% of calories from fat. So a 2000 calorie died would have a DRV of 600 calories. The amount of calories per gram of fat is often cited as 9 calories per gram. But according to the USDA National Nutrient Database for Standard Reference, 100 grams of soybean or canola oil (which is 100% fat) has 884 calories, corresponding to 8.84 calories per gram of fat. So a 2000 calorie diet would have a DRV of 68 grams of fat, and a 3000 calorie diet would have a DRV of 102 grams of fat (34 grams of fat per 1000 calories). So we can multiply 34 grams times the number of calories in thousands, e.g. a 2500 calorie diet would have 34 x 2.5 = 85 grams of fat. According to the USDA Nutrient Database (NDb), olive oil has 13.5 grams per tablespoon, canola oil has 14 grams per tablespoon. Other oils have about the same range of grams per tablespoon. So one teaspoon (1/3 tablespoon) has about 4.5 grams of fat. About 5 tablespoons of vegetable oil meets (slightly exceeds) the DRV for fat for a 2000 calorie diet. http://www.nal.usda.gov/fnic/foodcomp/search/ The daily value for each essential fatty acid, or for both combined, is different than the daily value for overall fat intake. Not all of your dietary fat need be the essential fatty acids (LA and LNA). Other fatty acids, such as the omega-9 ones, are also healthy as part of your overall diet. The recommended amounts of LA and LNA are called the Acceptable Macronutrient Distribution Range (AMDR). For omega-6 (LA) the AMDR value for adults is 5 to 10% of total caloric intake. So a 2000 calorie diet would have 100 to 200 calories from omega-6 fatty acids, which is 11 to 23 grams of LA. However, any source of omega-6 (LA) fat is not going to be 100% omega-6. If 25% of the oil is LA, then you need 11 x 4 = 44 grams of the oil to obtain enough LA from that source. For omega-3 (LNA) the AMDR value for adults is 0.6 to 1.2 percent of total caloric intake. So a 2000 calorie diet would have 12 to 24 calories from LNA, which is 1.35 to 2.7 grams of LNA. Again, any source of omega-3 (LNA) fat is not going to be 100% omega-3. If 7% of the oil is LNA, then you need 20 to 40 grams of the oil to obtain enough LNA from that source. (See the PDF file on AMDR for macronutrients at http://www.iom.edu/?id=54405) The AMDR values for LA and LNA, when compared, give a ratio of about 8 grams of LA for every gram of LNA (8:1). However, some researchers recommend an optimum ratio of LA to LNA of about 3:1. Udo Erasmus' book 'Fats that Heal, Fats that Kill' considers the optimum ratio to be between 5:1 and 2:1; he then goes on to state a long-term ideal ratio (to give one number) as being probably 3:1. So if we round the optimum range of LA to 12 to 24 grams, then the corresponding optimum range of LNA, with a three to one ratio, would be 4 to 8 grams. Since the optimum ratio and amount of essential fatty acids is subject to a range of opinions in different sources, ultimately the reader will have to decide the best dietary choices for himself or herself. Macronutrients.pdf SOURCE: Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (2002/2005). Growing Fat in the Garden According to the FAO (The Food and Agriculture Organization of the United Nations), the seven major oil crops in the world are soybeans, cottonseed, groundnuts (peanuts), sunflower seed, rapeseed (and/or canola), palm kernels, and copra (coconut). http://www.fao.org/docrep/meeting/W8499e.htm Cottonseed oil contains a natural toxic ingredient called gossypol, which the home gardener would be unable to remove; ingestion of even small amounts over a prolonged period can be harmful or lethal. So the home gardener cannot grow cottonseed for use as an edible oil. http://www.fao.org/agrippa/publications/4DMellonew-06.htm http://www.fao.org/AG/agA/AGAP/FRG/AFRIS/Data/541.HTM Rapeseed (not the canola variety) is high in erucic acid and in glucosinolates, which some sources cite as detrimental to health. The canola variety is a rapeseed which was improved to be low in erucic acid and low in glucosinolates. So most varieties of rapeseed (the non-canola varieties) would not be among the better choices for a home gardener. Later, this article will consider whether canola is a useful crop for the backyard garden. http://www.mayoclinic.com/health/canola-oil/AN01281 Although many trees produce nuts with edible and nutritious oils, tress are more difficult to grow in the backyard garden. Many of the trees used to produce edible oils are tropical trees, not suitable for growing in many areas of the world, including various types of palm trees. So this article will not consider palm oil and coconut oil. Even trees suitable for colder climates must grow for at least several years before producing a sizeable quantity of nuts. In any case, growing trees for their edible nuts and oils (almond oil, walnut oil, etc.) is outside the scope of this article. The other major oil crops (soybeans, peanuts, sunflowers) may be readily grown in many backyard gardens, depending upon suitability of the plant or variety for the particular climate. In addition, there are a number of other possible plant sources of essential fatty acids which may be suitable for a home garden. Eating Fat from the Garden After the home gardener has grown a plant source of essential fatty acids, there are basically two ways to extract the oil. The simplest way is to eat the seeds/nuts that contain the fat. Your digestive system will 'extract' the nutritious fat, as well as the protein that always accompanies these plant sources of fat. The other way is to press the seeds or nuts in a small home oil press. The efficiency of a small home press is limited, but it does provide oil for cooking and for various recipies. One of the least expensive oil presses is the Piteba manual oil press. The press weighs about 5 pounds, and is about 8 inches by 5 by 2.5. The manufacturer states that it can press numerous different types of oil seed without having to remove the shell, including rapeseed, safflower, sunflower, noog, sesame, pumpkin, peanut, hemp, soybeans, and some nuts. A small oil lamp is used to heat the press while extracting the oil; this increases the efficiency of the extraction. http://www.piteba.com/eng/index_eng.htm http://www.youtube.com/watch?v=Ko-IW8SdcKY Whole seeds from various plants will usually keep for at least a few months without refrigeration, and longer with refrigeration. But unrefined home pressed oil should be refrigerated and will only keep a few months. Oil can also be frozen in a plastic container in any ordinary freezer (allow enough room in the container for the oil to expand). The unrefined oil from any nut or seed will have a stronger flavor than the same oil when commercially refined. In generally, the oil will taste like the nut or seed from which it is pressed. You could use the oil along with other strong flavorings, to lessen the taste of the particular oil you are using. Or you could adjust your expectations. Possible garden sources of omega-6 (LA) fatty acids The following information on percentages of oil and percentages of essential fatty acids is taken from the USDA National Nutrient Database for Standard Reference (http://www.nal.usda.gov/fnic/foodcomp/search/) and also from the book 'Fats that Heal, Fats that Kill' by Udo Erasmus. However, the percentage of oil and percent of each type of fatty acid will vary based on the particular cultivar and the growing conditions (fertilizer, water, soil, temperature). Even the planting date can affect the nutrient content of some plants. Therefore the percent of oil and of fatty acids will vary. The following numbers are only a general guideline. Safflower seeds (100 g) 38% of the seed is oil (38 g) 74% of the oil is LA (28 g) Sources of safflower seed for the backyard gardener to plant may be difficult to find, but some varieties of safflower seed are also sold for birdfeed. When grown for omega-6 (linoleic acid) fat, the grower should choose an improved variety (developed for higher oil content). Of these improved varieties, some are high in linoleic acid (omega-6) and others high in oleic acid (omega-9). For more of the essential fatty acid LA (linoleic acid), the gardener should choose a linoleic variety; these include: S-541, Nutrasaff, and Centennial. These latter two are restricted by PVP, plant variety protection, but can still be grown and the seed saved for personal use in the home garden. Information on growing safflower: http://www.hort.purdue.edu/newcrop/afcm/safflower.html “The oil in linoleic safflower contains nearly 75% linoleic acid, which is considerably higher than corn, soybean, cottonseed, peanut or olive oils…. This crop does best in areas with warm temperatures and sunny, dry conditions during the flowering and seed-filling periods. Yields are lower under humid or rainy conditions…. Consequently, this crop is adapted to semiarid regions.” The home gardener is limited in this case by the need to find a suitable variety, by the requirement for a dry hot climate, and by the need to press the seed to obtain the oil. The taste of safflower oil is a light nutty flavor, and the color is a light tan. But unrefined freshly-pressed oil will have a stronger flavor and darker color than refined oil purchased in a store. Safflower seed is one of the richest sources of omega-6 fatty acid. Pumpkin seeds (100 g) 49% of the seed is oil (49 g) 43% of the oil is LA (21 g) Sources of seed should be easy to find. There are many varieties of pumpkins and they can be grown in a wide variety of different climates. The hull-less varieties (of which there are few) are a better choice if the seed will be eaten instead of pressed. Eating the seeds is perhaps the most efficient way to 'extract' the edible oil from the seed. Freshly-pressed pumpkin seed oil has a dark green color and a strong taste of pumpkin seed. Fresh home-pressed oil should always be refrigerated; even then, it will only keep for a few months. Information on growing pumpkins: http://www.hort.purdue.edu/newcrop/nexus/Cucurbita_pumpkin_nex.html Sesame seeds (100 g) 49.6% of the seed is oil (49.6 g) 42% of the oil is LA (21 g) Sesame seeds can be grown for their edible seeds; the seeds can be made into a paste called Tahini; the seeds can be pressed for oil. The oil has a very strong taste and may not be suitable for general use as a cooking or salad oil. It is typically used more as a flavoring in food, rather than as a major source of dietary fat. The strong taste of the oil limits its usefulness as a source of omega-6 fat. But the seed paste, mixed with sugar or other ingredients, is much more palatable, and is a good source of all essential amino acids, except lysine (which it has at 63% of ideal). http://www.bitterpoison.com/protein/12166/ The seeds are small, which makes harvesting them more difficult compared to larger seed, such as peanuts or soybeans. Sources of seed are not as easy to locate as pumpkin and soybeans. Seed Savers Exchange (members only) has a number of the harder to find seed types mentioned in this article, including sesame seeds. http://www.seedsavers.org/ Information on growing sesame seeds: http://www.jeffersoninstitute.org/pubs/sesame.shtml Peanuts (100 g) 49% of the nut is oil (49 g) 32% of the oil is LA (15.5 g) It is not so unusual for a home gardener to grow peanuts. A number of the major commercial sources of seeds for home gardens offer several varieties of peanuts for planting. The nut is easy to harvest, and is about one third omega-6 (LA) essential fatty acid. The nut can be cooked and eaten whole, or made into peanut butter, or pressed for oil. Peanuts are easy to shell, and the shelled nuts are among the easiest nuts or seeds to press for oil. Information on growing peanuts: http://www.hort.purdue.edu/newcrop/afcm/peanut.html Sunflower seeds (100 g) 51.5% of the seed is oil (51.5 g) 45% of the oil is LA (23 g) There are two general types of sunflowers grown for food, those grown in order to eat the seeds whole (snack type), and those grown in order to press the seeds for oil (oil type). The oil varieties have smaller seeds that are difficult to shell for eating, but they have higher oil content. The seeds do not need to be shelled in order to press them for oil. The snack type has larger seeds that are easier to shell, but less oil content. However, pressing seed for oil only extracts a limited percentage of the oil from any seed or nut. This is particularly true with small home presses. Eating the snack type seeds allows our digestive system to extract the oil, which it does much more efficiently than a press. So eating the seeds might provide more available LA than pressing the seeds for oil. On the other hand, sunflower oil has versatile uses in cooking and food recipies. Information on growing sunflowers: http://www.jeffersoninstitute.org/pubs/sunflower.shtml Possible garden sources of both omega-6 (LA) and omega-3 (LNA) fatty acids There are a couple of problems with the above described sources of omega-6 fatty acids. First, they lack any substantial amount of omega-3 fatty acids (LNA). Second, they require relatively hot growing conditions and are not very frost tolerant. Both of these problems are solved by some of the plant sources of fat below, which contain both LA and LNA, and which tend to thrive in somewhat cooler conditions than the above sources. Flax seeds (100 g) 42% of the seed is oil (42 g) 14% of the oil is LA (6 g) 55% of the oil is LNA (23 g) ratio of LA to LNA is about 1:3.8 There are two general types of flax, those grown for fiber (which have few seeds), and those grown for the seeds. Flax can be grown in areas with cooler temperatures and occasional frosts. The seeds do not need to be hulled before pressing for oil. Flax is an excellent source of LNA, but a poor source of LA. Therefore, the home gardener would need to grow another plant source of essential fatty acids, one high in LA. Using only flaxseed as the dietary source of essential fatty acids results in a deficiency of LA and possible health problems. Information on growing flaxseed: http://www.jeffersoninstitute.org/pubs/flax.shtml “Flax is currently grown on about 12 million acres worldwide, with the majority of the production in northern Europe and Russia.... flax seedlings can survive temperatures down to 28°F. upon emergence, and can tolerate the low 20s after they reach the two leaf stage.” Chia seeds (100 g) 31% of the seed is oil (31 g) 19% of the oil is LA (5.8 g) 56% of the oil is LNA (17.5 g) ratio of LA to LNA is about 1:3 Chia seed has about 3 times more LNA than LA. Although estimates as to the ideal ratio of LA to LNA vary from 2:1 to 8:1, with the ideal perhaps at 3:1, the ratio in chia seed is the reverse, 1:3, and so has too little LA. Combining use of chia seed oil with an oil high in LA, such as safflower, would provide a good ratio of LA to LNA. For example, 1 tablespoon of chia seed oil (about 14 g) has about 2.7 g of LA and about 8 g of LNA. To obtain a three to one ratio, we would need a total of 24 g of LA. So the safflower oil has to provide 21.3 more grams of LA to comprise this ratio. Safflower oil is 74% LA, so about 28 grams (about two tablespoons) must be added to the chia seed oil for a better ratio of essential fatty acids. One tablespoon of chia oil, plus two tablespoons of safflower oil, is about the correct ratio of LA to LNA. The same approach could be used for any combination of two or more oils containing LA and/or LNA. Information on growing chia is difficult to find. “It is hardy to zone 9 and is frost tender. It is in flower from July to August…. The plant prefers light (sandy) and medium (loamy) soils and requires well-drained soil. The plant prefers acid, neutral and basic (alkaline) soils. It cannot grow in the shade. It requires dry or moist soil.” http://www.pfaf.org/database/plants.php?Salvia+hispanica Styrian pumpkin seeds? (100 g) 46% of the seed is oil (46 g) 45% of the oil is LA (21 g) What percentage of the oil is LNA? Most varieties of pumpkin have little or no omega-3 (LNA) fatty acid. Reportedly, a type of pumpkin grown in Styria, the southeastern region of Austria, contains significant amounts of LNA. However, several websites which sell Styrian pumpkin seed oil, and which list the content of various fatty acids as a percentage of the oil, state little or no LNA (alpha-linolenic acid) in their Styrian pumpkin seed oil. The stated percentages vary from 2% to 0.1% http://www.oblepiha-us.com/about%20Pumpin%20seeds%20oil.asp states: alpha-linolenic acid, less than 1.0 http://www.oilgin.com/oil_about.htm does not list LNA, but states: Others 0.0-2.0% http://www.triedtastedserved.com/oils/pumpkin-seed.php states: 0.5% of alpha-linolenic acid (omega-3), then states (per 100 g): Total Omega-3 fatty acids 460 mg (which is 0.46%) http://www.dietobio.com/aliments/en/pumpkin.html cites 'USDA Nutrient Database for Standard Reference, Release 13 (November 1999)' and states: 0.181 grams of Alpha-linolenic acid (18:3) per 100 g http://www.oilsbynature.com/products/pumpkin-seed-virgin-oil.htm states: Alpha-linolenic acid C18:3 <1.0 http://www.sacredearth.com/ethnobotany/useful/oils.php states: Fatty Acids Linolenic 0.1% Several other sites selling Styrian pumpkin seed oil make a general claim of high amounts of “linoleic and linolenic acid,” without distinguishing the amounts of each fatty acid. A few websites state that the oil has a high amount of linolenic acid, but do not give numbers or any support for that claim. Unfortunately, from the information available, I've been unable to find a reputable claim of a particular variety of pumpkin seed with high levels of LNA. And so pumpkin seeds remain a good source of LA, but they cannot be considered to be a good source of LNA, unless a reliable source can be found for a variety of pumpkin with high LNA. Canola seed (100 g) 30% of the seed is oil (30 g) 18.6% of the oil is LA (5.6 g) 9% of the oil is LNA (2.7 g) ratio of LA to LNA is about 2:1 According to Udo Erasmus ('Fats that Heal…'), canola oil is 30% LA and 7% LNA; this gives us a 4:1 ratio. According to the USDA Nutrient Database, canola oil is 18.6% LA and 9.1% LNA; this gives us a 2:1 ratio. Either ratio is within a good range, given the lack of consensus on the best ratio. However, at the lower set of numbers (from the USDA), about 65 grams (575 calories) of canola oil would be needed to provide a good amount of both LA (12 g) and LNA (5.9 g). That amount of calories (575) is close to the recommended amount of fat in a 2000 calorie diet (600 calories). By comparison, 14 grams of high linoleic safflower oil combined with 12 grams of flaxseed oil provides about 12 grams (total) of LA and about 6.4 grams of LNA, at a cost of only about 230 calories. So canola has the advantage of combining both LA and LNA in one source, but it is not a particularly rich source of either fatty acid. Seed suitable for the home garden might be difficult to find. Also, the home gardener should probably avoid other forms of rapeseed, which are high in erucic acid and in glucosinolates, and which some sources cite as detrimental to health. Canola seed can be pressed without shelling. Information on growing canola seed: http://www.jeffersoninstitute.org/pubs/canola.shtml Soybeans (100 g) 17.7% of the bean is oil 50% of the oil is LA (9 g) 7% of the oil is LNA (1.2) ratio of LA to LNA is about 7:1 Although 7% of the oil is LNA, about the same as canola, the amount of LNA per 100 grams of seed is low, only 1.2 grams. Also, keep in mind that these numbers are approximate, since oil content and fatty acid composition will vary based on growing conditions and the particular variety of plant. As a result, soybeans are not a good source of LNA, and only a mediocre source of LA. However, soybeans are easy to grow; planting seed is easy to find and there are numerous varieties; also, they are easy to shell and can be eaten whole, rather than pressed for oil. Soybeans are also high in protein. Information on growing soybeans: http://www.hort.purdue.edu/newcrop/nexus/Glycine_max_nex.html Camelina Sativa seeds (100 g) (called false flax or gold-of-pleasure) 30 to 40% of the seed is oil 20 to 25% of the oil is LA (8 g) 35 to 39% of the oil is LNA (12 g) ratio of LA to LNA is about 1:1.5 “Camelina sativa emerged from this trial as a promising oilseed crop for production across Montana and the Northern Great Plains. Evaluation parameters included input costs, production costs, harvest costs, and yield. Camelina sativa was not always the highest yielding oilseed crop but it was the most economical crop to produce due to minimal input requirements.” http://www.hort.purdue.edu/newcrop/ncnu07/pdfs/pilgeram129-131.pdf Although not as high in omega-3 (LNA) as flax, Camelina sativa has a better ratio of LNA to LA. Total EFAs in Camelina is about 20% of the seed, and about 55% of the oil. The high amounts of antioxidants in the oil are said to give it a longer shelf-life, but the home gardener would be prudent to refrigerate all home-pressed oil. The oil and the seed are both available in the U.S. retail gourmet food market. Sources of seed for planting may be difficult to find. Seed Savers Exchange (members only) has only a couple of sources (2009). Information on growing false flax: http://www.hort.purdue.edu/newcrop/nexus/Camelina_sativa_nex.html http://www.teagasc.ie/research/reports/crops/4320/eopr-4320.asp The Best Garden Sources of Essential Fatty Acids So far in our consideration, flax seed is the richest source of LNA and safflower seed is the richest source of LA. Camelina Sativa is a good source of both essential fatty acids, LA and LNA, but the proportion of LNA is higher than desirable. However, if the home gardener lacks an oil press, perhaps peanuts, hull-less pumpkin seeds, and soybeans would be good choices. These can all be eaten without pressing or labor-intensive shelling/threshing of the seeds. Sunflower seeds can be shelled as they are eaten, and chia seeds do not need hulling; so these are additional options. Next we will consider good sources of EFAs (essential fatty acids) that have certain problems associated with them. These problems might be overcome by future commercial development of the plants, or by other factors. Problematic garden sources of essential fatty acids: Hemp seeds (100 g) 35% of the seed is oil 60% of the oil is LA (21 g) 20% of the oil is LNA (7 g) ratio of LA to LNA is about 3:1 Hemp seed is 35% oil, which is close to the oil content in safflower, and which exceeds the oil content of canola, chia, and soybeans. Based on its percentage of oil per 100 g of seed, hemp is a good source of oil. Now 60% of the oil is LA, which is higher than any other percentage of oil as LA, other than safflower. If we take into account the percent of oil and the percent of LA, then 100 g of hemp seed as about 21 grams of LA, which is exceeded only by safflower and equaled only by pumpkin seed. As a source of LNA, hemp is exceeded by flax, chia, and camelina. But those sources have an imbalance of essential fatty acids (EFAs) in that they offer too much LNA as a ratio to their LA. On the other hand, hemp exceeds the LNA offered by canola or soybeans. The ratio of LA to LNA in hemp is ideal (or within optimum range given a lack of consensus among researchers on the ideal ratio). At 60% LA and 20% LNA, the ratio of 3:1 is excellent, and the amounts of each EFA are also high. As a source of EFAs, hemp is near perfect. However, hemp is illegal to grow in the United States. (Technically, it is legal to grow hemp in the U.S. with a permit from the DEA; but the DEA has never issued any such permits.) In nations where hemp is legal to grow, often a special permit is needed, so that a home gardener would not practically be able to obtain such a permit. Certain large farms can obtain the permits and grow hemp for domestic sale. The U.S. permits the import of non-viable (unable to sprout) hemp seed and of hemp oil. But home gardeners are generally unable to grow this excellent source of essential fatty acids without fear of legal action or arrest. Some groups are working to attempt to legalize hemp. This is not an attempt to legalize the marijuana plant, which contains high amounts of the illegal drug THC. The hemp seed itself has no THC; the hemp plant's leaves and stems contain traces of THC. But many companies are able to sell hemp oil and hemp seed tested to zero parts per million of THC. So the issue is not the growing or sale of a recreational illegal drug. The problem is that hemp looks very similar to marijuana, and genetically they are closely related. If hemp is legal to grow in your nation without a permit, or in the unlikely event that a permit were accessible and affordable to a home gardener, you might consider growing hemp as a source of EFAs, as well as an excellent source of protein. Hemp seed is a better source of EFAs than any other plant, especially considering the limits of a home garden. Plants that need further investigation as sources of essential fatty acids: The FAO (Food and Agriculture Organization of the United Nations) identified Perilla, Sacha Inchi, and Noog (as well as several other plants) as important minor edible oil crops: “…many minor oil crops are of vital dietary and economic importance to large numbers of poor people around the world and some it is suggested could prove of much wider application” http://www.fao.org/docrep/x5043E/x5043E02.htm#Introduction Of the minor oil crops listed by the FAO, two will be reviewed in this article, because they provide significant amounts of omega-3 fatty acids, Sacha Inchi and Perilla. In addition, some researchers in the U.S. have suggested that Camelina sativa might become a useful large-scale edible oil crop, partly because of its high levels of omega-3 fatty acids. Perilla seed perilla frutescens (Beefsteakplant) 31 to 51% of the seed is oil 10 to 15% of the oil is LA (5 g) 64% of the oil is LNA (26 g) ratio of LA to LNA is about 1:5 Perilla oil is available in the U.S. through various Asian food stores; it is sometimes used in Korean and Japanese cooking. The oil has a strong dark taste, recognizable to those who are familiar with many Asian dishes, but which many Western palates might find unusual or perhaps objectionable. But it is generally the case that an unrefined oil will have a strong taste. In a food that is strongly flavored, any unrefined oil might find a palatable place within that set of flavors. But the individual will have to decide what is acceptable for him or her. In Asian food, the oil is used more for flavoring than general cooking. Perilla oil has a high percentage of LNA (omega-3), higher than any other source (though flaxseed is close). Therefore, this plant and its oil may warrant further consideration and development as a source of LNA. The high amount of LNA means that the oil does not keep well unless it is refrigerated, and then it keeps only a few months. Information on growing Perilla: http://www.fao.org/docrep/x5043E/x5043E0a.htm#Perilla The plant is difficult to grow since the seeds do not germinate easily. Sacha Inchi seeds (100 g) Plukenetia Volúbilis Linneo 35 to 60% of the seed is oil 36% of the oil is LA (17 g) 48% of the oil is LNA (23 g) ratio of LA to LNA is 1:1.3 Sacha Inchi is an interesting plant source of EFAs, unlike any of the other choices above. The plant is a perennial from the rainforest; it takes about 5 months to flower, and 3 additional months before the seeds are ready. But then the plant continues to bear seeds for up to 10 years. http://www.rodaperu.com/sachaInchi/ Hot and humid conditions year-round are needed for this plant to thrive, which means that in many locations, it could only be grown in greenhouses. The harvesting of the seeds is necessarily labor-intensive, since the plants are perennials (no combine harvester for this crop). The seeds are high in protein and valued as nutritious snack food; the oil is high in both LA and LNA. Cold-pressed Sacha Inchi oil has a mild flavor, not unlike canola oil, but slightly stronger. Seed sources are very difficult to find in the U.S. (none found so far). There is very little information available on growing Sacha Inchi. The plant has only recently caught the attention of the health food market in western nations. If anyone knows of a seed source (for planting) contact me. EFA Summary Omega-6 (LA; linoleic acid) only Safflower seeds (100 g) 38% of the seed is oil 74% of the oil is LA (28 g) Pumpkin seeds (100 g) 49% of the seed is oil 43% of the oil is LA (21 g) Sesame seeds (100 g) 49.6% of the seed is oil 42% of the oil is LA (21 g) Peanuts (100 g) 49% of the nut is oil 32% of the oil is LA (15.5 g) Sunflower seeds (100 g) 51.5% of the seed is oil 45% of the oil is LA (23 g) Omega-3 (LNA; linolenic acid) and Omega-6: Flax seeds (100 g) 42% of the seed is oil 14% of the oil is LA (6 g) 54% of the oil is LNA (23 g) ratio of LA to LNA is about 1:3.8 Chia seeds (100 g) 31% of the seed is oil 19% of the oil is LA (5.8 g) 56% of the oil is LNA (17.5 g) ratio of LA to LNA is about 1:3 Canola seed (100 g) 30% of the seed is oil 18.6% of the oil is LA (5.6 g) 9% of the oil is LNA (2.7 g) ratio of LA to LNA is about 2:1 Soybeans (100 g) 17.7% of the bean is oil 50% of the oil is LA (9 g) 7% of the oil is LNA (1.2) ratio of LA to LNA is about 7:1 Camelina Sativa oil (100 g) (called false flax or gold-of-pleasure) 30 to 40% of the seed is oil 20 to 25% of the oil is LA (8 g) 35 to 39% of the oil is LNA (12 g) ratio of LA to LNA is about 1:1.5 Hemp seeds (100 g) 35% of the seed is oil 60% of the oil is LA (21 g) 20% of the oil is LNA (7 g) ratio of LA to LNA is about 3:1 Perilla seed perilla frutescens (Beefsteakplant) 31 to 51% of the seed is oil 10 to 15% of the oil is LA (5 g) 64% of the oil is LNA (26 g) ratio of LA to LNA is about 1:5 Sacha Inchi seeds (100 g) Plukenetia Volúbilis Linneo 35 to 60% of the seed is oil 36% of the oil is LA (17 g) 48% of the oil is LNA (23) ratio of LA to LNA is 1:1.3 Best sources of garden fat: Best source of omega-6 (LA) Safflower seeds, since 28% of the seed is LA Best source of omega-3 (LNA) Flaxseed, since 23% of the seed is LNA (Sacha Inchi requires year-round hot and humid conditions. Perilla oil is not as well-developed as a source of oilseed.) Best combined sources of both EFAs Camelina Sativa, since it has both at a good 1:1.5 ratio (8% to 12%) (Hemp would be the best source, if it was legal.) |