Category: Health Tips

The Link Between Excess Fat & Inflammation

As Attune Health’s in-house nutritionist, a common conversation I have with many people is about the risks associated with having excess fat. First of all, it is important to note that our bodies need fat; they possess a number of functions including the production of hormones, temperature regulation, vitamin reabsorption, and protection. Typically, for men you would want to be between 13 and 20 percent body fat, while women would want to be between 17 and 28 percent.

The issue with fat comes when there is an excess amount of it. When we accumulate extra calories as a result of overconsumption or physical inactivity, that excess energy is stored as fat, otherwise known as adipose tissue. Adipose tissue plays a large role in inflammation and immunity, so this is an important topic to talk about.

 

WHAT IS ADIPOSE TISSUE?

 

Adipose tissue has traditionally been defined as connective tissue that stores excess calories. Subcutaneous adipose tissue, which is typically what we consider when we think about body fat, is is stored under the skin. Adipose tissue can also be stored around our organs in the form of visceral adipose tissue.

 

OBESITY: WHAT IS IT & WHAT ARE THE CONSEQUENCES?

 

Excess fat is typically associated with metabolic syndrome, a collection of conditions that includes high blood pressure (hypertension), high blood sugar (hyperglycemia), excess body fat around the waist, and abnormal cholesterol or triglyceride levels. This condition can increase your risk of heart disease, stroke, and diabetes.

If excess body fat accumulates to the extent that someone’s BMI measures above 30, that individual is considered to be obese. The most troublesome variation is central (abdominal) obesity, which is defined as an excess amount of body fat around the waist. This should make sense intuitively; think about it – your core is where you store all of your organs. If that is where you are storing fat, it is going to put stress on your body.

Additionally, obesity, specifically with excess visceral adiposity, is strongly associated with insulin resistance (a common precursor to diabetes), hypertension, and dyslipidemia, or an abnormal amount of fats – triglycerides, cholesterol, and/or fat phospholipids – in the blood. These, in turn, contribute to a high rate of morality and morbidity. Accumulating evidence indicates that a state of chronic inflammation has a vital role in the development of obesity-related metabolic dysfunction [1,2].

 

OBESITY & INFLAMMATION

 

In individuals with normal metabolic status, there is a balance of pro- and anti-inflammatory adipokines, as well as immune and metabolic homeostasis. Adipokines are cytokines, or cell-signaling proteins, that are specifically released by adipose tissue. As excess fat accumulates and adipose tissue expands during the development of obesity, this balance of pro- and anti-inflammatory adipokines shifts in favor of inflammation.

This balance is influenced by a number of different factors, including:

  • nutritional/metabolic status
  • the presence of infection or systemic inflammation
  • oxidative stress
  • smoking status
  • age
  • sex [3-9]

The pro-inflammatory status of adipose tissue contributes to a chronic state of inflammation and metabolic disorders associated with obesity.

The most well-known pro-inflammatory adipokine is leptin, and it increases in proportion to the amount of adipose tissue present. Leptin can directly enhance the production of several pro-inflammatory factors such as Interleukin-6 (IL-6), which can help predict the chances of developing Type II diabetes [10-11]. Moreover, leptin levels are positively correlated with the severity of different diseases, including:

  • Osteoarthritis
  • Multiple Sclerosis
  • Nonalcoholic Fatty Liver Disease
  • Hepatic Fibrosis
  • Renal Disease
  • Atherosclerosis
  • Thrombosis [12-20]

 

HOW TO IMPROVE OBESITY: CALORIC DEFICIT

 

One common way to reduce the size of fat cells is calorie restriction. By doing this, pro-inflammatory adipokines decline and anti-inflammatory adipokines increase, promoting an anti-inflammatory state. There is a downside, however: this effect is also associated with a suppression in immune system function. Therefore, overall, caloric restriction induces a reduction in inflammation, but at the cost of a decrease in immunity as well.

 

CONCLUSION & KEY POINTS

 

To summarize, excess fat promotes inflammation due to pro-inflammatory adipokines such as leptin, and therefore it is crucial to achieve and maintain a healthy weight. In doing so, your body will be producing more anti-inflammatory adipokines and promote immune and metabolic homeostasis.

Weight loss through a healthy diet and exercise are the best methods of sustaining a healthy weight. Creating lifelong habits is the best way to ensure long-term success.

 

REFERENCES

 

  1. Hotamisligil GS. Inflammation and metabolic disorders. Nature 2006;444(7121):860-7 doi: 10.1038/nature05485[published Online First: Epub Date]|.
  2. Shoelson SE, Lee J, Goldfine AB. Inflammation and insulin resistance. J Clin Invest 2006;116(7):1793-801 doi: 10.1172/JCI29069[published Online First: Epub Date]|.
  3. Mancuso P, Huffnagle GB, Olszewski MA, Phipps J, Peters-Golden M. Leptin corrects host defense defects after acute starvation in murine pneumococcal pneumonia. Am J Respir Crit Care Med 2006;173(2):212-8 doi: 10.1164/rccm.200506-909OC[published Online First: Epub Date]|.
  4. Ahima RS, Prabakaran D, Mantzoros C, et al. Role of leptin in the neuroendocrine response to fasting. Nature 1996;382(6588):250-2 doi: 10.1038/382250a0[published Online First: Epub Date]|.
  5. Sull JW, Kim HJ, Yun JE, Park EJ, Kim G, Jee SH. Serum adiponectin is associated with smoking status in healthy Korean men. Endocr J 2009;56(1):73-8
  6. Isidori AM, Strollo F, More M, et al. Leptin and aging: correlation with endocrine changes in male and female healthy adult populations of different body weights. J Clin Endocrinol Metab 2000;85(5):1954-62 doi: 10.1210/jcem.85.5.6572[published Online First: Epub Date]|.
  7. Somech R, Reif S, Golander A, Spirer Z. Leptin and C-reactive protein levels correlate during minor infection in children. Isr Med Assoc J 2007;9(2):76-8
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  10. Visser M, Bouter LM, McQuillan GM, Wener MH, Harris TB. Elevated C-reactive protein levels in overweight and obese adults. JAMA 1999;282(22):2131-5
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