Obesidade e câncer: mecanismos envolvidos e intervenções terapêuticas

Abstract

A transição demográfica iniciada no Brasil, a partir da década de 60, promoveu mudanças nos hábitos de vida da população, promovendo alterações no perfil nutricional e nas manifestações de doenças. No início do século XXI, ocorreu um marco no qual, pela primeira vez, o número de indivíduos com excesso de peso ultrapassou os de baixo peso, o que é preocupante, pois a obesidade é apontada como um dos principais fatores de risco para inúmeras patologias crônicas, incluindo diabetes, dislipidemia, doenças cardiovasculares e inúmeros tipos de câncer. A incidência e a mortalidade por câncer vêm aumentando no mundo, em parte devido ao envelhecimento e crescimento populacional, mas também pela mudança da distribuição e prevalência dos fatores de risco relacionados ao câncer. Vários fatores como mudanças metabólicas ou hormonais, influenciadas pelo aumento do tecido adiposo, resistência à insulina, hiperinsulinemia, inflamação crônica de baixo grau, maior biodisponibilidade de hormônios e estresse oxidativo, contribuem para os mecanismos de carcinogênese na obesidade. A alimentação balanceada, além de contribuir para o controle de peso, pode exercer o papel protetor em relação à carcinogênese. Há pesquisas em andamento que avaliam o potencial de vegetais verdes-escuros, alaranjados, crucíferos (repolho, brócolis, couve de Bruxelas), produtos de soja, feijão (carioca, preto, branco, vermelho), legumes, cebola, alho e tomate na prevenção do câncer. Outro fator importante é a prática regular de atividade física, que diminui o risco de câncer por melhorar a sensibilidade à insulina, o que estimula a imunidade e diminui os níveis de adipocina e marcadores inflamatórios. Dessa forma, esta revisão tem como objetivo analisar e relacionar informações associadas com a obesidade e o câncer.

Eating Habits, Physical Activity Practice and Clinical Prognosis of Colorectal Cancer Patients with Overweight/obesity

“…BMI is used worldwide as an indicator of body weight and as an index to diagnose overweight and obesity, thereby assessing the risk of developing other diseases, such as CRC. 15,[32][33][34] The present study observed that the majority of patients diagnosed with CRC had a BMI ≥ 25 kg/m 2 (68.3%).…”

“…[10][11][12] Hyperinsulinemia can promote proliferation and inhibit apoptotic mechanisms in cancer cells. [13][14][15] Additionally, in chronic lowgrade inflammation, unbalanced levels of cytokines with increased levels of proinflammatory adipokines and decreased levels of antiinflammatory adipokines are observed, 5, 15 which can contribute to tumor development. 16 Maintaining healthy eating habits, with a balanced diet rich in fruits and vegetables and a low intake of processed foods, foods rich in carbohydrates and fats, and red meats, contributes to preventing the development of overweight and obesity as well as cancer.…”

“…16 Maintaining healthy eating habits, with a balanced diet rich in fruits and vegetables and a low intake of processed foods, foods rich in carbohydrates and fats, and red meats, contributes to preventing the development of overweight and obesity as well as cancer. 15,[17][18][19] In 2018, in its latest project to update the evidence assessment (Diet, Nutrition, Physical Activity, and Cancer: A Global Perspective), IARC (http://gco.iarc.fr/today) concluded that several results corroborate that physical activity is directly associated with a decrease in the risk of CRC development. 20 In addition to regular physical activity, avoiding sitting for an extended period can protect against CRC.…”

Extended treatment with (1→3)(1→6)‐β‐d‐glucan (Botryosphaeran) reduces obesity and its comorbidities in high‐fat/high‐sugar diet‐fed rats

“…Obesity is associated with several diseases, being a risk factor for the development of other comorbidities that include glucose intolerance, dyslipidemia, hepatic steatosis, nonalcoholic fatty liver disease, diabetes, cardiovascular diseases, depression, and cancer 4–8 . This metabolic and multifactorial disease is the result of complex polygenic factors and an obesogenic environment 1–3,9 .…”

“…2,3 Obesity is associated with several diseases, being a risk factor for the development of other comorbidities that include glucose intolerance, dyslipidemia, hepatic steatosis, nonalcoholic fatty liver disease, diabetes, cardiovascular diseases, depression, and cancer. [4][5][6][7][8] This metabolic and multifactorial disease is the result of complex polygenic factors and an obesogenic environment. [1][2][3]9 Changes in eating behavior, as well as sedentary lifestyle habits, act on susceptible genes that are believed to be the main drivers for the worldwide increase in obesity among people.…”