Grapefruit is a citrus fruit related to lemon, orange and pomelo. In fact it is thought to be a natural hybrid between orange and pomelo.
For those of you who haven’t tried it, the fruit has a refreshing tangy sweet taste.
It is classified on the basis of color of the flesh: white, red or pink. Half a grapefruit is worth 54 calories.
Eating half a grapefruit daily can meet 64% of your daily Vitamin C requirement. It is rich in antioxidants, minerals and vitamins.
Lycopene is an antioxidant found in grapefruit which imparts the red, pink color to the flesh and also displays anti-tumor properties.
Pectin a soluble fibre present in grapefruit helps lower cholesterol. Naringenin a flavonoid found in copious amounts in grapefruit is said to have DNA repairing properties.
Does grapefruit really help with weight loss?
Coming to weight loss, something called the ‘grapefruit diet’ had been a fad diet in US since 1930s. This diet was based on the fact that grapefruit has fat burning properties.
Anyways we will go over what research has to say about the role of grapefruit in weight loss over the years.
1. Grapefruit consumption is associated with better diet quality
National Health and Nutrition Examination Survey 2003-2008 reported that grape fruit consumption in the form of whole fruit or juice is associated with higher intake of vitamin C, magnesium, potassium, dietary fiber, and improved diet quality.
Also, grapefruit consumers were associated with lower body weight, BMI, waist circumference and low cholesterol and blood lipids.
Also the risk of being obese or overweight was not linked with grapefruit consumption.
What does this mean?
NHANES survey found that consumption of grapefruit was associated with better diet quality and reduced risk of obesity.
2. Grapefruit consumption burns body fat and cholesterol
Dietary energy density is the number of kilocalories per gram of food. Reducing dietary energy density promotes satiety and reduces further calorie intake.
To exploit this idea, researchers investigated the effect of consuming grapefruit or grapefruit juice (foods that are low in energy density) before meals.
Over the time total energy intake reduced by 20-29% and individuals experienced 7.1% weight loss that included loss of body fat. Cholesterol levels also reduced.
Results of a clinical trial state that ruby red grapefruit consumption brings about non-significant decrease in weight and blood pressure and a significant decrease in blood lipid and cholesterol.
Red grapefruits' lipid lowering capacity can serve to be therapeutic in case of atherosclerosis.
What does this mean?
Regular consumption of grapefruit juice lowers body fat. It also reduces cholesterol and is healthy for the heart.
3. Grapefruit juice is better than anti-obesity drug
Grapefruit juice is found to be better than sibutramine, an anti-obesity drug. Sibutramine promotes satiety.
In an animal study, grapefruit juice is found to demonstrate its weight reduction effect 1 week after administration and this effect lasted for the entire duration of the study.
Also, grapefruit did not affect the brain in order to promote satiety.
Sibutramine, on the other hand, showed its weight reduction effect 1 week after administration and lasted only for 2 weeks. It also affected the noradrenaline levels in the brain.
What does this mean?
Research proves that is better than anti-obesity drug sibutramine.Grapefruit is as effective as sibutramine in controlling appetite.
4. Active constituents in grapefruit stimulate weight loss
Nootkatone is a compound found in grapefruit which prevents obesity by influencing AMP-activated protein kinase (AMPK).
AMPK is responsible for balancing energy at a cellular level and of the whole body and it suppresses the development of obesity.
Nootkatone increases the activity of AMPK leading to enhanced energy metabolism and reduced body weight and abdominal fat accumulation.
Citrus flavonoids are botanical compounds present in citrus fruits. Research claims that these compounds can offer protection from abnormal lipid metabolism. Naringenin is one such compound.
Naringenin is an active constituent of grapefruit which is proven to influence lipid and carbohydrate metabolism.
It regulates the activity of proteins PPAR and LXR (proteins that play a role in the development of obesity) in a way that it facilitates the breakdown of fats.
This property can be of use in treating metabolic diseases like diabetes and obesity.
Naringenin also impacts AMPK related pathways thus affecting energy balance and metabolism.
Animal studies prove that naringenin carries out following functions which can help in treating obesity
- Prevents weight gain
- Reduces inflammation
- Improves impaired lipid levels
- Exhibits antioxidant activity
- Demonstrates anti-diabetic activity by suppressing carbohydrate absorption and preventing elevations in post-meal glucose levels
What does this mean?
Active constituents of grapefruit target many biochemical pathways to facilitate reduction in body fat. Active ingredients like naringenin and nootkatone are also beneficial in treating metabolic diseases associated with obesity.
5. Half a grapefruit is enough to make you lose weight
A study was conducted in California to evaluate the effects of grapefruit and its products on body weight and related parameters.
Volunteers were randomly allotted to the following groups who received:
- Placebo capsules & apple juice
- Grapefruit capsules & apple juice
- Grapefruit juice
- Half of fresh grapefruit with placebo capsules
The grapefruit groups lost significantly more weight than the placebo group. The grapefruit groups showed a reduction in blood glucose and insulin levels up to 2 hours after the meal.
The group receiving half of the fresh grapefruit lost maximum weight (1.6 kg). Researchers concluded that consuming half a grapefruit before meals can help with weight loss.
A clinical trial conducted in the University of Arizona reports the effect of grapefruit on lowering body weight and other metabolic parameters.
In this study, individuals were assigned to either a control diet or grapefruit diet wherein they give half a fresh grapefruit thrice daily with each meal for 6 weeks.
Grapefruit consumption resulted in modest weight loss outcomes but a significant reduction in waist circumference and blood pressure.
Improvement in lipid profile was observed. However, researchers concluded that grapefruit consumption for 6 weeks does not result in significant weight loss as compared to control.
A detailed review of clinical trials conducted on the effect of grapefruit on body weight revealed that grapefruit consumption leads to modest weight loss outcomes but a significant decrease in blood pressure and lipid levels.
A short duration of trials and lack of effective dose can be the possible reasons for such results.
Before jumping to any conclusion, we should keep in mind that the duration of the first study is 12 weeks and the second one lasted for 6 weeks.
In both studies grapefruit was associated with weight loss, thus suggesting that this fruit can help fight obesity.
What does this mean?
Consuming half a grapefruit before major meals can improve weight loss outcome of low calorie diets.
6. Grapefruit is a natural anti-diabetic agent
Obesity and diabetes serve as risk factors to each other. Impaired glucose and insulin levels can affect carbohydrate digestion leading to weight gain.
Also, impaired insulin activity leads to spikes in glucose levels after the meal which is associated with increased appetite.
Animal studies report that the property of grapefruit juice to control blood glucose is comparable to that of metformin, a WHO-approved oral anti-diabetic drug.
But the drawback is, that if taken along with metformin, grapefruit increases the risk of developing lactic acidosis (high lactic acid levels in the bloodstream)in diabetic patients.
Alcoholic extracts of grapefruit seeds are proven to have glucose and lipid-lowering effect in animal models. This validates the traditional use of grapefruit seeds in treating type 1 diabetes.
Extracts of grapefruit peels inhibit activities of enzymes involved in carbohydrate metabolism namely α-amylase and α-glucosidase.
This property can be useful in treating diabetes and hypertension. It can also be helpful in preventing post-meal glucose spikes and promoting satiety.
What does this mean?
Grapefruit’s blood glucose lowering activity is as good as that of metformin, an anti-diabetic drug. Its blood glucose lowering capacity can help modulate carbohydrate metabolism, thus preventing weight gain and improving metabolic health.
7. Helichrysum & Grapefruit duo help in weight loss
Helichrysum is a species of plants belonging to the sunflower family native to Africa. Its essential oil is said to have many health benefits: anti-spasmodic, anti-coagulant, anti-microbial properties etc.
The combination of helichrysum and grapefruit extracts is said to have beneficial effects on body weight.
Research states that this duo in combination with low-calorie diet can help improve weight loss results.
Studies suggest that both the extracts can help prevent weight gain, improve insulin and glucose levels, reduce oxidative stress (imbalance between pro-oxidant and antioxidant agents in the body) and inflammation.
Refined carbohydrate food items lead to weight gain. Helichrysum and grapefruit extract balance post-meal glucose levels by inhibiting activities of enzymes and proteins involved in carbohydrate digestion and absorption.
What does this mean?
Many research studies suggest that the combination of Helichrysum and grapefruit extract is good for weight loss.
8. Aromatherapy with grapefruit can help in weight loss
An experimental study reports that grapefruit oil can inhibit the formation and development of fat cells.
The fragrance of grapefruit oil gives a refreshing feeling which in scientific terms involves activation of sympathetic nerve (nerves that regulate body’s unconscious action such as flight or flight response).
It is known that activation of the sympathetic nerve in the fat tissue can cause lipolysis or breakdown of fats, thus preventing weight gain.
An experimental study conducted on rats demonstrated stimulation with scent of grapefruit oil and lemon oil, activated lipolysis and suppressed weight gain.
Aromatherapy massage with grapefruit oil in combination with other oils is found to reduce belly fat and waist circumference.
What does this mean?
Even the scent of grapefruit oil can help you lose weight. Consider investing in grapefruit essential oil and consult an aromatherapy specialist regarding the use of grapefruit oil for weight loss.
How much grapefruit for weight loss?
Half a grapefruit consumed before or with meals thrice or twice daily for 6 weeks or more can aid in weight loss.
You can also consume a glass of grapefruit juice daily or include grapefruit in your salads.
A proprietary weight loss supplement containing extract of orange, grapefruit and red-orange was tested for its effect on body weight.
Reduction in the waist and hip circumference and abdominal fat was observed. The supplement also lowered inflammation and oxidative stress.
If opting for grapefruit extract supplements, consult a health practitioner before taking them.
Precautions
Grapefruit can have many drug interactions.
Compounds present in grapefruit especially naringenin slows down metabolic processes in the intestine and liver thereby affecting the body’s ability to breakdown and eliminate pharmaceutical drugs.
Therefore if you are already consuming any medicines for whatsoever reason, consult your doctor before consuming grapefruit or grapefruit juice on a daily basis.
Conclusion
Consuming grapefruit prior to meals can help suppress appetite. Also, grapefruit has active ingredients that can burn fat, lower cholesterol, and blood sugar levels and improve metabolic health.
So go ahead and enjoy the tart, tangy flavor of the fruit while shedding a few pounds.