Peanuts – Health Benefits
Published on: 24th Jan 2013
The peanut (நிலக்கடலை: in Tamil) plant (Arachis hypogea) is a legume that is native to South America (it now grows in warm areas around the world). The peanut plant grows to about 60 cm tall. It has small orange-veined, yellow-pedaled, pea-like flower is borne in auxiliary clusters above ground. (1-2 cm long). The flowers bloom for only about half a day; the blossoms are self-pollinating. About 4 days later, a stem (also called a peg) will grow from the flower and head into the soil. At the end of each stem, the seed pods (peanuts in the shell) will grow. The peanut is an annual plant (it completes its life cycle in one year).
Peanut growing requires at least five months of warm weather with rainfall (or irrigation equivalent) of 600 mm or more during the growing season. In Asia the peanut is grown under irrigation. The best soils are well-drained sandy loams underlain by deep, friable loam sub-soils. At harvest the entire plant, except the deeper roots, is removed from the soil. The nuts are best cured by allowing the harvested plants to wilt for a day, then placing them for four to six weeks in stacks built around a sturdy stake driven upright into the soil. The pods are placed toward the inside of each stack to protect them from weather.
The fruits have wrinkled shells that are constricted between pairs of the one to four (usually two) seeds per pod.
|Fat contained /144g||Mineral contained /144g||Vitamin contained /144g|
|- Total Fat: 75.6g
- Saturated Fat: 12.5g
- Monounsaturated Fat: 37.4g
- Polyunsaturated Fat: 22.0g
- Total Omega-6 fatty acids: 21859mg
|- Potassium: 1045mg
- Phosphorus: 572mg
- Sodium: 461mg
- Magnesium: 253mg
- Calcium: 87.8mg
- Zinc: 4.7mg
- Manganese: 2.7mg
- Iron: 2.2mg
- Copper: 0.8mg
- Selenium: 4.8mcg
|- Choline: 79.6mg
- Niacin (Vitamin B3): 19.9mg
- Alpha Tocopherol (Vitamin E): 10.0mg
- Pantothenic Acid (Vitamin B5): 1.7mg
- Vitamin C: 1.2mg
- Vitamin B6: 0.7mg
- Thiamin (Vitamin B1): 0.1mg
- Riboflavin (Vitamin B2): 0.1mg
- Folate: 173mcg
- Vitamin B1: 20.0mcg
1. Peanuts Benefits Heart Health
In 2008, P.M. Kris-Etherton and colleagues from the Pennsylvania State University carried out a pooled analysis of four epidemiological studies conducted in the United States to investigate the effect of and nut consumption on coronary heart disease. They found that those who consumed highest peanut and nut consumption had an approximately 35% of coronary heart disease. The researchers attribute this to the nuts’ cholesterol-lowering effect and antioxidant and anti-inflammatory properties. Nutrients in nuts and that may be responsible for these effects include plant protein, fiber, the minerals potassium, magnesium and calcium, vitamin E, and the phytochemicals phytosterols, polyphenols, resveratrol and the amino acid arginine[know more].
Researchers from Purdue University studied 15 healthy men and women for 30 weeks, in a complex study assessing the effect of peanut consumption under 3 different dietary conditions. From this study they concluded that peanut consumption reduces serum triglyceride levels by 24%. This was the case even when peanuts were added to regular diets. Peanut consumption reduce cardiovascular risk 6 – 8%. Furthermore, peanuts added significant magnesium, folate, fiber, copper and arginine to the dietary intake.
On the other hand the researchers also noted no increase in body weight during the 30-week trial. They speculated that peanuts may create a sense of satiety (fullness,) thus reducing their subjects’ overall caloric consumption.
The FDA now allows peanuts along with walnuts, almonds, hazelnuts, pecans and pistachios to be advertised as providing a health benefit[know more].
Deaths due to heart diseases like cardiovascular disease and coronary heart disease have shown strong, consistent reductions with increasing peanut and peanut butter consumption in the Iowa Women’s Health Study for example (Kushi, 1996). And in a study of Seventh-day Adventists in California, it was found that frequency of peanut consumption had a highly significant inverse association with death from Ischemic Heart Disease (Fraser, 1992)[know more].
Higher nut consumption has been associated with lower risk of coronary heart disease events in several epidemiologic studies. The study examined the association between intake of nuts and incident cardiovascular disease in a cohort of women with type 2 diabetes. For the primary analysis, there were 6309 women with type 2 diabetes who completed a validated FFQ every 2–4 y between 1980 and 2002 and were without cardiovascular disease or cancer at study entry[know more].
Frequent nut consumption was associated with a reduced risk of both fatal coronary heart disease and non-fatal myocardial infarction. These data, and those from other epidemiological and clinical studies, support a role for nuts in reducing the risk of coronary heart disease[know more].
2. Maintains Cholesterol levels
Peanuts, peanut butter, and peanut oil are contained with heart-healthy monounsaturated and polyunsaturated fats. These fats lower total cholesterol, LDL cholesterol and triglycerides while keeping HDL cholesterol high.
A controlled human study that fed diets high in either peanut oil, peanuts and peanut butter, or olive oil, which were all high in monounsaturated fat, lowered total cholesterol and LDL cholesterol and triglycerides while maintaining HDL cholesterol compared to an average American diet[know more].
The US Food and Drug Administration to release a health claim in 2003, which says “Scientific evidence suggests but does not prove that eating 1.5 ounces (42.5 grams) of most nuts, such as peanuts, as part of a diet low in saturated fat and cholesterol may reduce the risk of heart disease.”[know more]
Most people without realising that plays a fundamental role in improving heart health focus on lowering LDL cholesterol for reducing heart disease. HDL cleans out excess LDL cholesterol from artery walls and moves it to our liver where it’s broken down and used make bile and excreted[know more]. This helps keep artery walls from hardening and blocking blood flow to our heart. According to the Mayo Clinic, our HDL cholesterol levels should be between 40 and 60 mg/dl.
Scientists at Shahid Beheshiti University in Iran studied the impact of peanut consumption and cardiovascular risk in men with high cholesterol levels. Participants followed a diet with or without 77 gram of peanuts for four weeks. Cholesterol levels were measured before and after the study. Researchers reported in the October 2010 issue of “Public Health Nutrition” that those who consumed peanuts experienced increases in HDL cholesterol compared with those who didn’t[know more].
3. Protects against Alzheimer’s and Age-related Cognitive Decline
Alzheimer’s disease is a progressive brain disease that causes deterioration of thinking and language skills, memory loss and changes in behaviour. Characteristics of the condition include plaques caused by clumps of beta-amyloid, protein that build up outside and around nerve cells in the brain. And this tangles by twisted, thread-like fibers made of the protein tau that accumulate within brain cells, disrupting normal cell function.
Due to this, over time, the brain’s nerve cells are unable to communicate with other cells and eventually die. As the disease progresses, affected areas of the brain begin to shrink, leading to symptoms such as memory loss, confusion, inability to perform daily tasks, depression, aggression, delusions and hallucinations.
While scientists , they do think a combination of genetics, environmental factors, age and brain nerve cell damage from free radicals may set off this condition.
Scientific research shows , also known as vitamin B-3, . A study by M.C. Morris and colleagues in an August 2004 issue of the “Journal of Neurology, Neurosurgery and Psychiatry” found a link between niacin and study participants who developed Alzheimer’s. According to the researchers, participants who consumed only 12.6 mg of niacin per day, the lowest among all participants, were 80% more likely to develop the condition than those who consumed nearly double the amount.
Researchers also found the rate of mental decline was 44% lower among those who consumed highest level of niacin intake compared with those with the lowest level.
Peanut and peanut butter is not only a source of protein, but it also is packed with dietary fiber, vitamins such as vitamin E and niacin, and minerals, including phosphorous, zinc, iron, calcium, folate and magnesium. 144g of peanut contains 19.9mg of niacin.
Resveratrol is a type of antioxidant, known as a polyphenol, found in foods including red wine, grapes and peanuts. Studies show this antioxidant may protect against Alzheimer’s by preventing plaque formation in the brain. In a November 2005 study in “The Journal of Biological Chemistry,” Philippe Marambaud and colleagues found adding the antioxidant to the cells of mice lowered levels of the protein responsible for plaque accumulation in Alzheimer’s patients.
Peanuts and peanut butter contains high levels of the polyphenol p-coumaric acid. The antioxidant is known to counter the effects of free radicals to prevent oxidative damage. Preliminary research suggests p-coumaric acid may impact cognitive function in Alzheimer’s patients. A study in the August 2007 issue of the “Journal of Neuroscience Research” found a compound containing p-coumaric acid improved learning and memory impairments in mice with dementia[know more].
Oil-roasted peanuts were more effective at scavenging free radical oxygen than their dry-roasted counterparts, as determined by a photochemiluminescence assay[know more].
Various studies have reported on the neuroprotective effects of polyphenols, widely present in food, beverages, and natural products. For example, resveratrol, a polyphenol enriched in red wine and other foods such as , protects hippocampal cells against beta-amyloid (Abeta)-induced toxicity, a key protein involved in the neuropathology of Alzheimer’s disease[know more].
This study was conducted in 1993–2002 in Chicago, a community of 6158 residents aged 65 years and older. Nutrient intake was determined by food frequency questionnaire. Four cognitive tests were administered to all study participants at 3 year intervals in a 6 year follow up. A total of 3718 participants had dietary data and at least two cognitive assessments for analyses of cognitive change over a median 5.5 years. Clinical evaluations were performed on a stratified random sample of 815 participants initially unaffected by AD, and 131 participants were diagnosed with 4 year incident AD by standardised criteria.
In this study the researchers learned that dietary niacin may protect against AD and age related cognitive decline[know more].
4. Peanuts and Diabetes
Research released late 2010 in the Journal of the American Medical Association found that eating nuts substantially lowers the possibility of developing Type 2 diabetes.
The diabetes study, by Dr. Rui Jiang from the Harvard School of Public Health in Boston, has found that eating 30 grams a day, five times a week, cuts the risk of Type 2 diabetes by around a third, without leading to weight gain.
The study was conducted with a huge group of nurses – 83,818, whose health has been tracked for 16 years. In the last 30 years the rates of type 2 diabetes have tripled in the last thirty years[know more].
David Jenkins , MD, PhD, DSc, Principal Investigator and a pioneer in the area of glycemic control for diabetics said, “Nuts, including , can by displacing high glycemic index carbohydrates and replacing them with vegetable fats and vegetable proteins which have been shown in the long term to be associated with better cardiovascular health and diabetes prevention.”
Peanuts have more protein than any other nut and are a source of mono and polyunsaturated oils. The paper reports that, “increased proportions of fat and protein, especially of plant origin, may confer metabolic benefits and reduce the risk of developing coronary heart disease and diabetes.”
The study, “Nuts as a Replacement for Carbohydrates in the Diabetic Diet”, was conducted at the University of Toronto. During the study, 117 men and women with type 2 diabetes were randomized into three groups where they received either a full portion of mixed nuts including peanuts, a half portion of both nuts and muffins, or a full portion of muffins. The muffins were made of healthy whole wheat with protein from egg and skim milk powder. Participants’ fasting blood glucose was tested every other week.
After three months, participants receiving the full portion of nuts showed the biggest decrease in glycated hemoglobin (HgA1c), a measure of blood glucose control. The difference was significantly more than the decrease shown in the participants receiving the half portion of nuts and muffins, and in those solely receiving muffins[know more].
5. Peanuts and Cancer
A twenty-year study by the Nurses’ Health Study points out women who eat as little as a handful (or 42.5 grams) of nuts or two tablespoons (28 grams) of peanut butter per week were 25% less likely to develop gallstones.
are present in about 80% of people with gallbladder cancer. There is a strong association between gallbladder cancer and cholelithiasis, chronic cholecystitis, and inflammation. Symptoms of gallbladder cancer usually do not appear until the disease has reached an advanced stage and may include weight loss, anemia, recurrent vomiting, and a lump in the abdomen[know more].
Many women citing the fact that peanut nuts and peanut butter are high in fat so believing these may contribute to weight gain and cardiovascular issues are unwilling to add even small amount of these to their diets. However, a study spreading over two years reports that participants who ate nuts and / or nut products twice a week or more 30% less probably to gain weight than their counterparts.
Antioxidant content in peanuts is among the highest from plants even more than some fruits – strawberries and blackberries. Antioxidants are thought to be connected to heart health.
New studies show resveratrol, a constituent of grapes, and certain other plants, can fight the proliferation of fat cells and improve the uptake of sugar from the blood. This explains why grape products, including wine, have developed a reputation as heart healthy, obesity-fighting and beneficial for people developing diabetes[know more].
Resveratrol in various peanut cultivars were ranged from 1.6 to 3.7 µg per gram[know more].
The Journal of Agricultural and Food Chemistry is one of many publications to publish studies that demonstrate the positive aspects of resveratrol. The health benefits of resveratrol on humans are unproven. In mouse and rat experiments, anti-cancer, anti-inflammatory, blood-sugar-lowering and other beneficial cardiovascular effects of resveratrol have been reported. Most of these results have yet to be replicated in humans[know more].
Finally, peanut butter can help prevent cancer. Those consuming peanuts just twice a week showed a 58% lowered risk of colon cancer in women and a 27% lowered risk in men according to World’s Healthiest Foods[know more].
But have been found in a quarter of .
Five out of 20 samples bought in major supermarkets contained potentially harmful levels of aflatoxin in tests ordered by trading standards officers[know more].
, a type of fungus found in peanuts and grains increase the risk of liver cancer. These chemicals are produced by moulds (or molds) found in foods such as nuts, cereals, and spices, especially in tropical countries.
The EU has set safety limits for aflatoxin content of imported foods. However, the FSA considers that consumption of a very small amount of aflatoxin on a single occasion is unlikely to have cancer-causing effects.
Dr David Phillips of The Institute of Cancer Research says: ‘Peanuts sold within Europe and America are safe because there are strict regulations,’ he says.
‘The best advice to tourists travelling elsewhere is to avoid peanuts that look mouldy. The problem is most likely to be in areas of the world where peanuts and grains are grown or stored in humid conditions. We know that this is the case in regions of China and West Africa,’ he says[know more].
National Institute of Environmental Health Sciences (NIEHS) and Massachusetts Institute of Technology (MIT) inform if the peanut butter comes from peanuts that were grown or stored in hot and humid conditions could be contaminated with aflatoxin, a mold directly linked to liver cancer and the Massachusetts Institute of Technology.
Researchers at Johns Hopkins University found eating vegetables such as celery, carrots, parsnips and parsley can decrease the carcinogenic effects of aflatoxin. They also found chlorophyllin, which abundant in green, leafy vegetables reduces the risk of liver cancer of those exposed to aflatoxin. The urine samples of those who consumed chlorophyllin at each meal showed 55% reduction of aflatoxin. It’s believed that chlorophyllin reduces aflatoxin levels by blocking the absorption of the toxin in the gastrointestinal tract.
Johns Hopkins University researchers found those who tested positive for the Hepatitis B virus and were also exposed to aflatoxin in their diet had about 60 times the risk of developing liver cancer than that of unexposed to aflatoxin individuals.
Global warming-related temperature spikes and droughts could increase the existence of aflatoxin in crops[know more].
The results of the two studies by China Medical University (CMU) and National Chiayi University (NCU) challenged the common view that eating many peanuts or peanut butter is risky because aflatoxin – on peanut shells – can cause liver cancer.
CMU researchers found that eating frequently can help prevent colon and rectal cancer after they studied the eating habits of 23 941 residents in eight counties in Taiwan.
Yeh Chih-ching, assistant professor at CMU’s Department of Risk Management, told Deutsche Presse-Agentur (dpa) that during the course of the study from 1991 to 2001, 109 people developed colon or rectal cancer. “We compared the cancer patients’ eating habits with that of those who did not have cancer and found that the latter had been eating more peanuts,” he said.
Yeh said eating peanuts twice a week can cut women’s risk of developing colon or rectal cancer by 58% and men’s chances by 27%.
Yeh said he believes that phytic acid, phytosterol and resveratrol in peanuts have cancer-prevention effects. His study found no link between aflatoxin and the development of liver cancer, he added, but said it found that .[know more]