In my previous two articles, I explained what polyphenols are and wrote about their many health benefits. I left out one health benefit of polyphenols that deserves its own article and often gets mentioned in relation to specific foods: weight loss.

Polyphenols and weight loss have been linked in numerous studies, and many of them are the active ingredients in weight loss supplements. What follows is a discussion of the major types of polyphenols that impact weight in humans.

Hydroxycinnamic Acids

Recent studies have shown that Hydroxycinnamic Acids are efficient in the obesity treatment and several other related health issues. In adipose tissues, these molecules derivative inhibit NF-κB activation and macrophage infiltration in obese persons. These acid derivatives have also shown to inhibit the expression of the powerful MCP-1, PAI-1, and TNFα.

Hydroxycinnamic Acids are also known to boost the secretion of anti-inflammatory agents known as adiponectin from adipocytes. The acid derivatives also function to prevent adipocyte differentiation and reduce lipid profile in a human body. It is through these diverse mechanisms that hydroxycinnamic acid induces loss in weight and alleviate related adverse health problems.

Caffeic Acid

Caffeic acid is a crucial chemical found in many foods and plants. Coffee is the primary source of caffeic acid in our diet. This compound can also be found in several other food sources including
berries, pears, apples, and artichoke. Wine is also known to contain a significant amount of this chemical.

Caffeic acid is widely used in supplements for enhancing athletic performance and weight loss. It is also used to alleviate the effects of exercise-related fatigue, HIV/AIDS, herpes, cancer, and other health complications.

How Caffeic acid works

Caffeic acid is believed to have anti-inflammatory and antioxidant effects in our bodies. Studies show that it affects our bodies’ immune system. It may also inhibit the growth of viruses and cancer cells. Several studies show that it may reduce fatigue related to exercise and a mild stimulant effect.

Cinnamic Aldehydes and Monolignols

Cinnamic aldehyde is found in the bark of camphor, cassia, and cinnamon plants. It produces cinnamon flavor and is a major content of the bark oil of cinnamon.

How does Cinnamic aldehyde induce weight loss?

Cinnamic aldehyde works to control weight in several ways:

It enhances the rate of metabolism

Including cinnamon in your diet will assist in speeding up the rate of metabolism. Taking cinnamon frequently enables your body to metabolize carbohydrates and sugars at a quicker pace. More importantly, the metabolized carbs and sugars are utilized by your body system, so they don’t get stored as fats! Since cinnamon uses less energy to metabolize, it will circulate in the body at a quicker rate. This enables your body to burn more calories.

It lowers the level of your blood glucose

Recent research shows that adding cinnamon to your meal can reduce its glycemic index by a whopping 29 percent! Taking low glycemic foods lowers erratic levels of blood glucose in your body, and that’s crucial in shedding off that excess weight! When the sugar level in your blood is reduced, you don’t feel those intense cravings. By keeping insulin level under check, the concentration of blood glucose also reduces.

It lowers the level of LDL cholesterol

LDL cholesterol is a form of bad cholesterol which leads to accumulation of fatty plaques within the arteries. Fatty plaques accumulation makes your body to become susceptible to cardiovascular disorders. A recent study found that diabetic patients who took cinnamon daily showed lower LDL cholesterol level than the initial level before the test.

Phenolic Acids

Phenolic acids are a crucial group of plant phenolics which is found in both white and red wine and also in the pulp of grapes. Phenolic acids are sub-divided into hydroxycinnamic acid and hydroxybenzoic acid. Examples of the hydroxycinnamic acid include caffeic acid, p‑coumaric acid, ferulic acid and caftaric acid. On the other hand, examples of the hydroxybenzoic acid include gallic acid, ellagic acid, and p-hydroxybenzoic acid.

The most common phenolic acids contained in grapes include gallic and caftaric acid. The major phenolic acids found in wines are gallic and caffeic acids. Extensive metabolism of phenolic acids is done by bacterial colonies found in the colon. Phenolic acids metabolites are absorbed and carried to the liver. This is where they are further broken down into hippuric acid and excreted. Phenolic acids are believed to induce the reduction in weight because of their antioxidant activities.

Benzoic Acids

There are incredibly a high number of plant foods that contain benzoic acid. Benzoic acid naturally occurs in most berries as well as other fruits including plums, cloudberries, cranberries, and prunes. Also, cinnamon is known to contain a high amount of benzoic acid.

As a preservative, benzoic acid is found in beer, chewing gum, maraschino cherries, and jellies. Cloudberries can be stored for an extended period of time without fungal or bacterial spoilage thanks to its high content of
Benzoic acid. It is also used in processed foods including meats and cheeses. As potent antioxidants, benzoic acids have shown to assist in weight reduction.

Stilbenes

Stilbenes are a group of chemicals, resveratrol being the most common among the group. The concentration of Stilbene in red wine is around 20mg/ while it ranges between 40 to 90 mg.kg-1 in the skins of red
grape. Resveratrol is found in grapes as both trans-resveratrol and cis-resveratrol. The two compounds are metabolized by gut enterocytes and then absorbed in our bodies.

Resveratrol has been widely researched, and it is evident that it is broken down at a very low rate than several other phenolic compounds like flavan-3-ols (epicatechin) or catechin. Resveratrol is always detected in the urine unmetabolised, but urine has mainly glucuronidated and sulphated conjugates. The weight reducing benefits of resveratrol relates to its exceptional ability to inhibit LDL cholesterol oxidation. Both trans and cis-resveratrol glucuronide metabolites are detected in the particles of LDL cholesterol after red wine ingestion.

Coumarins and Flavonoids

Flavonoids and coumarins are heterocyclic molecules that have beneficial effects on our health. Such benefits include reducing the risk of obesity, diabetes, cancer, brain diseases and cardiovascular diseases. These beneficial effects are believed to be associated with their radical scavenging effect, due to antioxidant mechanisms along with other possible activities such as interaction with various enzymes and anti-inflammatory activities.

Catechin

Epicatechin and catechin are examples of flavan-3-ols. They represent a sub-group of phenolic molecules that are categorized in the flavonoid category. Flavan-3-ols are largely contained in the seeds and skins of grapes. That said, white wine is a not a good source. Catechin has been widely researched in relation to its ability to assist in the maintenance of the proper body weight, and prevention of both cancer and cardiovascular disease. Evidence shows that catechin helps the body to perform the above functions.

Catechin concentration in red wine is around 100 mg/L while epicatechin is found at about 75 mg/L. Taking red wine boosts catechin plasma levels, and this may protect your plasma lipoproteins against oxidation. Catechin and epicatechin are extensively broken down in the small intestines’ enterocytes, and glucuronide and sulphate conjugates are seen in plasma. Conjugates and catechins from metabolism of enterocyte can also be metabolized further by the microflora of colon to phenolic acids. Phenolic acids are later absorbed in large intestines. Catechins are primarily found in argan oil, broad bean, tea, and cacao beans. It is also found in cocoa
powder but to a lesser degree because the processing removes nutrients.

Epigallocatechin-3-gallate (EGCG) is one of the most abundant catechins found in green tea in a concentration of (7.4 g per 100 g). In a recent study, EGCG was found to induce weight loss effects on mice. It was also found that green tea consumption also alleviated other metabolic related issues which are associated with obesity.

Genistein/Daidzein

Daidzein is an isoflavone found in soybean products. It shows estrogenic activity and may be used in estrogen replacement therapy as a natural substitute in postmenopausal women. Daidzein has also proved to reduce fat pad weight when tested in female mice. This study showed that oral genistein treatment could be used to induce adipose tissue apoptosis, lower body weight, and mobilize body fat. That said, genistein may be used in prevention or treatment of increased adiposity after menopause.

Dietary daidzein has also proved to have a direct effect on the metabolism of lipid in the adipose tissue and liver. Genistein increases free fatty acids and decreases triglycerides in serum. This is further supported by more studies which show that genistein inhibited lipid synthesis and induced lipolysis. In a recent study, it was found that genistein may be associated with regulation of lipid metabolism in adipose tissue through peroxisome
proliferator-activated receptors.

Wrapping it up, the above studies showed that genistein is efficient in lowering body fat and body weight in older female mice. Both in vivo and in vitro results demonstrate that daidzein has the ability to induce apoptosis of adipocytes, which suggests that part of the weight reduction is due to fat calls ablation, which could enable better weight loss maintenance. The outcomes of this study demonstrate that genistein may be very useful in prevention and treatment of increased adiposity after menopause.

Sources

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