A study published in the journal PloS one showed that, although obesity was the same between smokers and nonsmokers, smokers had more belly and visceral fat than nonsmokers. A healthy, balanced diet can help a person lose weight, and is also likely to have a positive effect on their overall health.
People may want to avoid sugar, fatty foods, and refined carbohydrates that have low nutritional content. Instead, they can eat plenty of fruit and vegetables, lean proteins, and complex carbohydrates. A person trying to lose excess abdominal fat can monitor their alcohol intake. Alcoholic drinks often contain additional sugar, which can contribute to weight gain. A sedentary lifestyle can lead to many serious health problems, including weight gain.
People trying to lose weight should include a good amount of exercise in their daily routine. A review indicates that exposure to sunlight in animals could lead to a reduction in weight gain and metabolic dysfunction. The review notes that few studies have looked at the effects of sunlight on humans with respect to weight gain, and that more research is required. Stress can cause a person to gain weight. Stress-relieving tactics include mindfulness and meditation , and gentle exercise like yoga.
Getting enough quality sleep is essential when a person is trying to shed weight, including belly fat. Smoking is a risk factor for increased belly fat, as well as many other serious health concerns. Quitting can significantly reduce the risk from excess belly fat, as well as improve overall health.
A person has a higher risk of various health issues if they have excess belly fat. Studies utilizing rodents indicate that even with a comparable amount of fat entering the lumen of the digestive tract, the chylomicrons produced by males transport more dietary fat than those produced by females; and the VLDLs produced by females transport more dietary fat than those produced by male Vahouny et al. From the animal to human studies discussed above, we can conclude that men transport more dietary fat through chylomicrons most likely because these chylomicrons are bigger and more than those of women.
There are several similarities and differences between chylomicrons and intestinal VLDLs. Regarding their similarities, both are apolipoprotein Bcontaining lipoproteins. They are also secreted to the capillary-rich lamina propria by the enterocytes see Figure 1. However, their transport routes are quite different, which may determine the fat depot they will preferentially supply their dietary fat to.
Chylomicrons preferentially promote the accumulation of the abdominal visceral fat. High-fat meal, which triggers more chylomicron production, decreased the proportions of meal fat stored in the subcutaneous fat of both men and women Votruba and Jensen, The unaccounted for meal fat in that study was likely stored in the abdominal visceral fat.
It is important to note that the unaccounted for meal fat was found previously to be correlated with the amount of abdominal visceral fat Romanski et al. Since the lymphatic capillaries of the intestine allow bigger particles to enter their lumen relative to the blood capillaries, the lymphatic system is the predominant transport route for most of the chylomicrons.
In addition to the transport by the lymphatics, VLDLs are capable of entering the lumen of the blood capillaries Takahara et al. Particles as large as 30 nm in diameter have been shown to pass through the walls of the abdominal visceral blood capillaries Simionescu et al.
Due to the fact that chylomicrons transport more dietary fat in males than in females, it is not surprising that males also have a higher lymphatic transport of dietary triglycerides than females Vahouny et al. Relative to the blood circulation, the lymphatic circulation is a low-pressure system that depends on the contraction of the surrounding muscles, such as the diaphragm and other abdominal muscles, to propel the lymph fluid.
Consequently, the movement of the chylomicrons within the lamina propria and low-pressure lymphatics becomes a challenge during the postprandial state. This, again, is supported by the prolonged elevation of plasma chylomicrons in men Knuth and Horowitz, as well as the higher recovery of the infused lipids in the intestinal mucosa when the intestine is challenged with more fat Lo et al.
Abdominal visceral fat accumulation has also been shown to correlate significantly with the delayed in postprandial lipid metabolism Taira et al. Electron microscopy studies also show that during the postprandial state the lipoproteins in the lamina propria are bigger than those in the lymphatic lumen, further supporting the notion that chylomicrons do not enter the lymphatic lumen as readily as their smaller counterparts VLDLs Takahara et al.
Importantly, unlike the lumen of the blood capillaries, the lamina propria and the lymphatic lumen are visibly congested with chylomicrons. The retention of chylomicrons in the lamina propria may predispose their triglycerides to the LPL hydrolysis.
Although it has been reported that mesenteric fat expresses LPLs Shimomura et al. As mentioned above, the LPL activities in the subcutaneous fat depots are generally higher in women, particularly in the lower part of the body Arner et al.
Therefore, it is tempting to speculate that relative to VLDLs, chylomicron triglycerides are more likely to be hydrolyzed by LPLs due to their higher retention in the lamina propria. Alternatively, the LPLs that are present in the lymph Huang et al.
Angptl4, which is secreted by adipocytes and liver during fasting Cushing et al. As the Angptl4 expression is reduced during postprandial state, the chylomicron triglycerides can then be potentially hydrolyzed by the disinhibited LPLs in the lymph.
Interestingly, the LPL expression in the mesenteric fat can be reduced by exercise Shimomura et al. This suggests that exercise does not simply increase the energy expenditure but may also inhibit the dietary fat uptake by the abdominal visceral fat. Additionally, exercise may help reduce the retention of the chylomicrons in the intestinal mucosa Havas et al.
Contraction of the surrounding muscles during exercise should help propel the congested chylomicrons into the lymph and reduce further the susceptibility of their triglycerides to LPL hydrolysis. The liberated fatty acids that are the products of the LPL hydrolysis will then be delivered to the mesenteries either through the veins or lymphatics within the mesenteries see Figure 1.
Note that these veins and lymphatics are the convergences of the blood and lymphatic capillaries of the lamina propria, respectively. Since these veins and lymphatics are surrounded by the abdominal visceral adipocytes, the liberated fatty acids supply the abdominal visceral adipocytes prior to the subcutaneous adipocytes.
Consequently, the LPL hydrolysis of the chylomicron triglycerides in the lamina propria should preferentially lead to the accumulation of abdominal visceral fat instead of subcutaneous fat.
The transport of the liberated fatty acids by the veins within the mesenteries is supported by the fact that the unesterified fatty acid concentration is elevated in the portal vein after a bolus feeding of triglycerides Kristensen et al. Of note, the hepatic portal vein receives blood from the mesenteries before draining them into the systemic blood circulation. The idea that chylomicron retention in the extracellular matrix of the intestine can lead to the abdominal visceral fat accumulation is supported by the Prox1 haploinsufficiency studies Harvey et al.
The leaky intestinal lymphatics conceivably allow more chylomicrons to leave the lymphatic lumen and be retained in the extracellular matrix. Their enormous size may further prolong their retention, allowing their dietary fat to be hydrolyzed and stored by the surrounding abdominal visceral adipocytes. The study also suggests that the free fatty acids that are presumably liberated from the hydrolysis of chylomicron triglycerides may serve as the inducer of adipogenesis.
Lymphatic leakiness, which can be reduced by exercise Hespe et al. The leakiness of the aging lymphatics may explain why the sex differences in the abdominal visceral fat accumulation become less pronounced with aging Camhi et al. It is becoming more apparent now that the roles of lymphatics in the development of android obesity cannot be disregarded.
Figure 3 summarizes our proposed mechanisms of why men are more likely to develop abdominal visceral fat than pre-menopausal women. Note that the aging and exercise effects are not depicted in the figure. The proposed mechanisms for the sex differences in the development of the abdominal visceral fat.
The size of lipoproteins is proposed to serve as an important factor in regulating the abdominal visceral adiposity. Due to the higher intake of dietary triglycerides and the potential hormonal regulation, men produce bigger and more chylomicrons.
These chylomicrons trigger congestion within the lamina propria and lymphatics, subjecting their triglycerides to LPL hydrolysis. The subsequent uptake of the hydrolysis products by the surrounding adipocytes results in the accumulation of the abdominal visceral fat.
Of all of the factors contributing to the accumulation of abdominal visceral fat, lifestyle is arguably the most important. Based on our proposed mechanisms, spreading out the amount of dietary fat intake into several smaller meals should reduce the likelihood of abdominal visceral fat accumulation by reducing both the size and number of chylomicrons.
Reducing the lipid load to the small intestine is also beneficial to the functions of the collecting lymphatics as high lipid load reduces their contraction frequency and amplitude Kassis et al. By maintaining the lymphatic contraction, smaller meals may reduce the retention time of the chylomicrons in the lamina propria. This would consequently reduce the likelihood of abdominal visceral fat accumulation. In overweight minority youth studies, the higher calorie-consuming nibblers, indeed, accumulate less abdominal visceral fat than the lower calorie-consuming gobblers House et al.
The studies also take gender into account, that is, males are more likely to gobble and accumulate abdominal visceral fat than females. Another important aspect of lifestyle is exercise. Besides increasing the energy expenditure, exercise may slow down the accumulation of abdominal visceral fat by increasing the flow of the chylomicrons within the lamina propria and lymphatics as well as reducing both the LPL expression in the mesenteric fat and the leakiness of the lymphatics.
There are other potential factors that may contribute to the development of abdominal visceral fat. But considering that it is a strong independent predictor of mortality, understanding the mechanisms of its development is critical.
Based on our proposed mechanisms, exercising and eating a diet low in fat—or at least spreading the fat intake into several smaller meals—should help in slowing down the development of abdominal visceral fat. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
The authors would like to thank Ann Phan for her contribution in editing the manuscript. The authors would also like to apologize to all researchers whose work is not cited in this manuscript. National Center for Biotechnology Information , U. Journal List Front Physiol v. Front Physiol.
Published online Dec 5. Andromeda M. Author information Article notes Copyright and License information Disclaimer. Louis, United States. Reviewed by: Nada A. Abumrad, Washington University in St. Nauli, ude. Received Jun 20; Accepted Nov The use, distribution or reproduction in other forums is permitted, provided the original author s and the copyright owner s are credited and that the original publication in this journal is cited, in accordance with accepted academic practice.
No use, distribution or reproduction is permitted which does not comply with these terms. This article has been cited by other articles in PMC. Associated Data Data Availability Statement The data supporting the conclusions of this article are from previously published articles.
Abstract Men have a higher tendency to accumulate abdominal visceral fat compared to pre-menopausal women. Keywords: visceral, adipocyte, gender, lipoprotein, chylomicron, intestine, absorption, belly.
Body Fat The sex differences in body composition have been well established Karastergiou et al. Abdominal Visceral Fat This paper focuses specifically on the visceral fat in the abdomen. Declines in testosterone that may occur with aging or other factors cause these cells to expand, often resulting in that pot belly you keep trying to suck in.
Until menopause comes along to shake up your life, women typically notice fat accumulation in their hips, thighs, and buttocks. This likely supports childbirth and breastfeeding. As you age, however, and your estrogen production declines, your fat redistributes itself and lodges in the belly -- some as subcutaneous fat and some as the deeper visceral fat.
Certainly, though, every individual is unique. You may be a woman who has been apple-shaped with a round tummy since birth or a man whose pear shape is easy to spot. Either way, belly fat poses the most danger to your health and, along with thigh and buttock fat, is often the most difficult type to get rid of. The only way to reduce the size of your fat cells is to lose pounds via a healthy diet that limits your caloric intake enough that they release their fat.
Select basic ads. Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights. Measure content performance. Develop and improve products. List of Partners vendors. Belly fat is the accumulation of abdominal fat that results in increased waist size. It is also known as central adiposity or abdominal obesity. Body fat, also known as adipose tissue, serves essential functions.
For example, it cushions and insulates the body from extreme temperatures. Due to its function in hormone production, adipose tissue is considered an endocrine organ. Two main types of adipose fat can accumulate around the abdomen: visceral located around the organs and subcutaneous found beneath the skin.
Visceral fat surrounds multiple vital organs, including the stomach, intestines, and liver. Both types of body fat are associated with cardiometabolic disease potential. However, visceral fat is more strongly linked to increased metabolic risk factors, insulin resistance, inflammation, and overall mortality.
While there are many causes of belly fat, there are also many healthy ways to reduce it and the health risks it poses. There are a host of potential causes of belly fat. Some are within our control to modify, but some are not. One of the most common causes of belly fat is consuming more calories than your body needs.
A sedentary lifestyle requires fewer calories. But no matter how active you are, if you consistently eat more calories than your body needs every day, you are creating an energy imbalance , which causes weight gain. Our metabolism naturally slows down as we age, meaning we burn fewer calories, and total body fat gradually increases. Women tend to gain a higher fat percentage than men as they get older.
In people who experience menopause, estrogen levels drop, which can change body fat distribution. This causes more fat to be directed to the midsection as opposed to the lower body.
Heredity can also be a factor. You might be genetically predisposed to gain weight in your midsection more than in other parts of your body. How our genes interact with the environment is also a factor. Today, that biological drive may be working against us. Hormones and hormonal changes can also affect belly fat accumulation. Leptin, a hormone that prompts feelings of fullness, is positively correlated to how much fat the body stores.
Early studies about leptin suggested that as body fat and leptin levels increased, the amount of leptin absorbed through the blood-brain barrier would decrease, reducing the signals regulating body weight.
However, in the 25 years that leptin and obesity have been studied, it is still not fully understood how they are interrelated.
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