There have been many failed attempts to provide evidence of a sixth sense, but now scientists have at least, they claim, come up with a sixth taste – the taste of fat. 
 
 Fat, which now joins sweet, sour, salty, bitter, and umami (savoury) has a unique and unpleasant taste that researchers have called oleogustus. They suggest its identification could lead to new ways of fighting obesity and heart disease, and to the creation of improved fat replacements. 
 
 “Our experiments provide a missing element in the evidence that fat has a taste sensation, and that it is different from other tastes,” says Professor Richard Mattes, director of the Ingestive Behaviour Research Centre at Purdue University in Indiana, US. 
 
 “Identifying the taste of fat has a range of important health implications. At high concentrations, the signal it generates would dissuade the eating of rancid foods,” he adds. 
 
 “But at low levels, it may enhance the appeal of some foods by adding to the overall sensory profile, in the same way that bitterness alone is unpleasant but at appropriate levels adds to the appeal of wine and chocolate.” 
 
 Current fat replacements may have been less successful than was hoped because they mimic the texture of fat, but not the taste, says the professor. Our food choices are often based on memories of how we felt after eating an item, but the taste of fat may contribute to those associations, he adds. 
 
 There has been a consistent recognition over the centuries of four primary taste qualities – sweet, sour, bitter and salty. Umami, referring to a meaty or savoury taste and first reported in 1908, has increasingly been accepted as a fifth basic taste. 
 
 50 best foods for healthy living 
 
 
 
 
 
 
 
 50 show all 50 best foods for healthy living 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 1/50 Digestion Live yoghurt - Many with digestive issues avoid dairy, but live yoghurt may be worth a shot, as it is full of gut-friendly bacteria. Because the lactose in live yoghurt is effectively broken down, it is gentler on the system than milk. Rex 
 
 2/50 Digestion Chia seeds - Just two tablespoons of chia seeds provide a third of your recommended daily intake of fibre. notahipster, Flickr 
 
 3/50 Digestion Sauerkraut - Fermented foods like sauerkraut (fermented cabbage) is packed with probiotics, aiding digestion. Qwerty Binary 
 
 4/50 Digestion Lentils - High in insoluble fibre, lentils are great for digestion, as well as being regarded as beneficial in alleviating irritable bowel syndrome and diverticulosis. Rex Features 
 
 5/50 Digestion Buckwheat - Despite the name, buckwheat is completely wheat and gluten free and a great, high fibre alternative to anyone with a wheat intolerance. Getty Images 
 
 6/50 Immune system Oranges - Citrus fruits such as oranges are high in Vitamin C, which helps to prevent colds and infection. Getty Images 
 
 7/50 Immune system Mushrooms - Shiitake mushrooms have been shown in studies to boost the production of white blood cells, thus improving the body’s ability to fight infection. powerplantop, Flickr 
 
 8/50 Immune system Clams - Contain zinc and selenium, which helps to slow the body’s immune response and control inflammation. 
 
 9/50 Immune system Garlic - Packed with antioxidants, garlic was used to fight gangrene in World War I, but more practically can help to keep colds at bay. It is also quite anti-inflammatory and anti-fungal, and used to treat everything from psoriasis to athlete’s foot. 
 
 10/50 Immune system Broccoli - One cup of broccoli provides you with almost 100% of your RDA of vitamin C, which is thought to stave off colds and other illnesses. It is also rich in vitamin A, K, folate and potassium. Cruciferous vegetables such as broccoli contain a sulphurous compound that studies show can lower the risk of cancer. Getty 
 
 11/50 Skin, hair and nails Avocado - The good fats in avocado hydrate the skin, while omega 9 can help reduce redness. Avocado is also rich in vitamin E, which helps guard against sun damage and vitamin C, which helps produce elastin and collagen for skin firmness. Getty 
 
 12/50 Skin, hair and nails Sunflower seeds - a handful contains more than a third of your daily vitamin E needs. F Ceragioli via Wikimedia Commons 
 
 13/50 Skin, hair and nails Pumpkin - One of the richest sourcs of Vitamin A, which is essential for the formation of connective tissue, i.e. skin. Getty Images 
 
 14/50 Skin, hair and nails Olive oil - The monounsaturated fatty acids in olive oil plump the skin for a more youthful look, plus antioxidant polyphenols may curb ageing free-radicals. SAIF DAHLAH/AFP/Getty Images 
 
 15/50 Skin, hair and nails Green tea - Polyphenols in green tea could help to offset sun damage. Getty Images 
 
 16/50 Weight loss Cinnamon - This spice is a great additive for breakfasts and bakes if you are trying to cut sugar and sweeteners, and it is also thought to help balance blood sugar. Getty Images 
 
 17/50 Weight loss Apples - Apples are high in pectin, a soluble fibre that helps to keep you feeling fuller for longer. Getty Images 
 
 18/50 Weight loss Eggs - One of the best sources of protein, eggs help to keep you energised and prevent unhealthy snacking, while providing a host of vitamins and minerals for general good health. Getty Images 
 
 19/50 Weight loss Tuna- High in protein, low in saturated fat and rich in omega 3, tuna is a fantastic option for maintained weight loss. The omega 3 in oily fish improves the body’s response to insulin, lowering metabolism and helping to prevent the dreaded sugar spikes. Getty 
 
 20/50 Weight loss Oats - High in fibre for slow-release energy, oats also are thought to lower cholesterol. Getty Images 
 
 21/50 Heart health Beetroot - This is a good source of iron and folic acid. It is also rich in nitrates, which help to reduce blood pressure. Raimond Spekking 
 
 22/50 Heart health Garlic - High in manganese, selenium and antioxidants, garlic is thought to help lower blood pressure and reduce cholesterol. Getty Images 
 
 23/50 Heart health Asparagus - Rich in the amino acid asparagine, which serves as a natural diuretic and helps rid the body of excess salts. This is beneficial for people have high blood pressure or other heart-related diseases. Getty Images 
 
 24/50 Heart health Salmon - Studies have found that eating oily fish such as salmon can lower blood pressure and reduce cholesterol. Rich in Omega-3 fatty acids, Getty Images 
 
 25/50 Heart health Pomegranate - Rich in vitamins A, C and E, and high in fibre, pomegranates are thought to help protect against heart disease. A 2004 study showed evidence that daily consumption helped to alleviate narrowed arteries and reduce cholesterol. Getty Images 
 
 26/50 Brain health Mackerel - Oily fish including mackerel is rich in Omega 3, which studies have suggested is linked to a reduced risk of dementia, schizophrenia and depression, as well as enhanced memory. Getty Images 
 
 27/50 Brain health Hazelnuts - HIgh in Vitamin E, which studies say can help to prevent cognitive decline in older people. Getty Images 
 
 28/50 Brain health Blueberries - low in calories and high in antioxidants, blueberries are regarded as a nutritional powerhouse. Some studies have found a link between blueberry consumption and improved spatial learning and memory. Getty Images 
 
 29/50 Brain health Cacao - Contains phenylethylamine, which acts as a mild mood enhancer, and a 2009 study shows signs that it can help to reduce stress. However, adding sugar and milk to cacao to make your favourite chocolatey treat offsets any health benefits - try to keep it as close to its natural state as possible. Keith Welle via Wikimedia Commons 
 
 30/50 Brain health Pumpkin seeds - Just a handful of pumpkin seeds a day provide your total RDA of zinc, which is important for enhancing your memory. 
 
 31/50 Energy Sweet potatoes - Starchy veg like sweet potatoes are a great source of low-GI carbohydrates for slow-burn, long-lasting energy. Sweet potatoes are also rich in soluble fibre and vitamins A, C and B6. Getty Images 
 
 32/50 Energy Beef - Low energy levels are often a sign of iron deficiency or anaemia. Lean cuts of beef are a good source of iron, as well as being a protein powerhouse to aid muscle development and stamina. Getty Images 
 
 33/50 Energy Brown Rice - Complex carbohydrates like brown rice break down into energy-boosting sugars more slowly than white rice, meaning more energy for longer, and more balanced blood sugar levels - i.e. no nasty sugar crash within hours of eating. Arria Belli, Flickr 
 
 34/50 Energy Bananas - A great source of energy that keep sugar levels balanced, plus the sweet taste will help to satisfy cravings. Getty Images 
 
 35/50 Energy Quinoa - This supergrain contains more protein than rice or any other grain, ideal for building muscle, along with being a nutrient-rich source of carbohydrates. AFP/ Getty Images 
 
 36/50 Bone health Sardines - Sunshine is the best source of bone-building Vitamin D, but if a British summer doesn’t allow for that, sardines are a surprising source, as well as being rich in calcium. Getty Images 
 
 37/50 Bone health Brussel sprouts - Just three-quarters of a cup of this divisive winter vegetable provides your RDA of vitamin K, which is essential in helping the absorption of calcium for healthy bones. Getty Images 
 
 38/50 Bone health Chickpeas - High in protein and fibre, chickpeas are also packed with iron, phosphate, calcium, magnesium, manganese, zinc and vitamin K, which contribute to building and maintaining strong bones. Scott Teresi, Flickr 
 
 39/50 Bone health Spinach - If dairy isn’t your thing, spinach could be your saviour - a cup of cooked spinach contains a quarter of your calcium needs. Getty Images 
 
 40/50 Bone health Almonds - Rich in potassium, which prevents the excretion of calcium in urine, as well as being rich in protein and other nutrients for maintaining bone health. M.Verkerk/J.J.G.Claessens/Creative Commons 
 
 41/50 Men’s Health Prawns - Rich in zinc, which is essential for sperm quality and fertility. Getty Images 
 
 42/50 Men’s Health Tomatoes - high in lycopene, an antioxidant which, according to the World Cancer Research Fund, can help reduce the risk of prostate cancer. Strangely, cooked and tinned tomatoes are recommended, as the lycopene is more readily absorbed. PIERRE ANDRIEU/AFP/Getty Images 
 
 43/50 Men’s Health Brazil nuts - High in selenium, which boosts the immune system and strengthens the thyroid gland. Quadell 
 
 44/50 Men’s Health Cauliflower - Rich in vitamin C, potassium and boron, which is said to aid in increasing testosterone levels and muscle-building. Getty Images 
 
 45/50 Men’s Health Turkey - With obesity an escalating problem for men, turkey is a great swap for your morning bacon. HIgh in lean protein, it is full of B vitamins, which can aid in lowering cholesterol. Getty Images 
 
 46/50 Women’s Health Walnuts - These nuts contain antioxidants and phytosterols that may help reduce the risk of breast cancer. Getty Images 
 
 47/50 Women’s Health Green beans - Low in fat, bean are a great source of protein and fibre and can also help to guard against breast cancer and heart disease. Isoflavones in beans, chickpeas and lentils help with the regulation of hormones, easing PMS and menopause symptoms. Getty Images 
 
 48/50 Women’s Health Flax - One of the oldest sources of fibre in the world, flaxseed can ease digestion as well as providing omega 3 fatty acids. It is also thought to be of help with menopause, but some experts say it should be avoided if pregnant. Sanjay Acharya via Wikimedia Commons 
 
 49/50 Women’s Health Cranberries - Rich in anthocyans, red berries such as cranberries help to play a role in cell repair and are thus thought to reduce cancer risk. Also high in vitamin C and folic acid, essential for women of childbearing age, and cranberry juice is a fantastic way to get rid of cystitis. Getty Images 
 
 50/50 Women’s Health Tofu - A great source of phytoestrogens, which can help with the symptoms of menopause and polycystic ovarian syndrome (PCOS). Getty Images 
 
 In the new study, reported in the journal Chemical Senses, the researchers investigated the taste sensation of non-esterified fatty acids (NEFA), or free fatty acids, which are fat’s basic building blocks. 
 
 In two experiments, volunteers wearing nose clips were asked to sample a range of different taste qualities, including NEFA, and sort them into groups of similar qualities. The texture of each of the samples was manipulated to be the same, so the only difference was taste. 
 
 Results show that the men and women identified fat as having a taste, different from all the other samples. 
 
 “Many people described it as bitter or irritating and consistently unpalatable,” says Professor Mattes. 
 
 “The research is difficult because we do not have a widely agreed-upon word to describe the sensation.” ||||| Forget sweet or sour, researchers say people may have a “sixth” taste for fatty foods. 
 
 Researchers out of Purdue University said that the taste of fat dubbed “oleogustus” can be added to the list of distinctive tastes that include sweet, salty, sour, bitter and umami. 
 
 To decipher if “oleogustus” could be identified by eaters the researchers conducted a small study to see if people could identify the “unique taste of fat.” They gave participants nose clips so they couldn’t mistake the aroma of food for taste and then had them try different concentrated samples and sort them by taste including sweet, salty, sour, bitter and blank. 
 
 In the study 64% of participants could distinguish a fatty acid sample from the group. While a fatty food taste test may seem to have been a dream come true, subjects reported samples with shorter fatty acid chains tasted sour and with longer fatty acid chains tasted pungent or irritating. 
 
 One reason for the distaste of the fat-heavy samples may have been the higher concentrations used. To concentrate taste researchers used concentrations of fatty acid chains that are higher than those found in food, but similar to the kinds of fatty acid chains found in cooking oils or fermented products. 
 
 Experts say the early experiment needs more research but could help shed light on how we react to certain foods. 
 
 Study co-author Richard Mattis told ABC News said that by understanding how the body “tastes” fat, we might also be able to understand if it affects how the body metabolizes foods. He said elevated levels of triglycerides, a main component of fat, is also associated with high levels of cardiac risk in a person. 
 
 “From a basic biology perspective it would be nice to know how our sensory systems work, identifying fat as a basic taste is equivalent…to knowing chartreuse is part of the visual [spectrum],” he explained. 
 
 Robin Dando, assistant professor of Food Science at Cornell University, said more and more studies have come out finding that fat can have its own flavor and that it could impact what we know about how receptors in the body perceive fat. 
 
 “I think it’s a really interesting piece of research the notion that fat is a taste itself is an important concept,” Dando told ABC News. ”This kind of … evidence that says we have a whole extra mechanism [for taste] is really scientifically important and interesting.” 
 
 Dando explained that previously researchers simply thought people identified fat by texture and that it didn't have a specific taste. 
 
 Amy Jamieson-Petonic, a dietician at University Hospitals Case Medical Center, said having a sixth taste could be extremely helpful when helping patients break down their diet. 
 
 “This might potentially be able to help us figure out different ways to tell people get their nutrients,” she said. She reiterated that she thought more study was needed before dietitians and others incorporate the taste of “fat” into their work. 
 
 ABC News' Sonia Singh contributed to this article.
– Ponder the taste of fat for a minute. Is your mouth watering? It shouldn't be. While the closest you've probably come to eating pure fat was on an untrimmed steak, Purdue University researchers have isolated the taste of fat for the first time—and folks, it isn't pleasant. They began by plugging the noses of participants who tasted a variety of samples instilled with chemicals representing the five basic tastes—bitter, salty, sour, sweet, and umami (savory)—and fatty acids, considered the "building blocks of fat," per Forbes. The unique taste of the fatty acids, which researchers dubbed "oleogustus," varied by chemical structure: short-chain fatty acids tasted sour and long-chain fatty acids tasted bitter. But what came as a surprise to researchers—considering how fat, when paired with other tastes and smells, usually enhances food—was that all variations tasted terrible. "We have a situation where one form of fat is adding to the appeal of food and may encourage intake. While with another, the taste signal is aversive, discouraging consumption," a researcher says. What gives? Researchers suggest that since fatty acids show up in rotting food, their off-putting taste may serve as a warning that what you're putting in their mouth shouldn't be there. At low levels, though, the acids' bitterness could enhance food. After all, chocolate and coffee can also be bitter, reports the Independent. Others note it may be the thick, creamy texture of fat that we adore so much, rather than the actual taste. The study author tells ABC News further study on how humans taste fat and confirmation of a sixth taste could help researchers understand how our bodies digest foods. Meanwhile, the research could lead to better replacements that mimic fat's texture and taste. (Here are 5 low-fat foods you should stop eating now.)