not limited to anxiety, depression, substance abuse, and other forms of mental and physical maladaptation. Stress caused by acculturation has been heavily documented in phenomenological research on the acculturation of a large variety of immigrants. This research has shown that acculturation is a "fatiguing experience requiring a constant stream of bodily energy," and is both an "individual and familial endeavor" involving "enduring loneliness caused by seemingly insurmountable language barriers". One important distinction when it comes to risk for acculturative stress is degree of willingness, or migration status, which can differ greatly if one enters a country as a voluntary immigrant, refugee, asylum seeker, or sojourner. According to several studies, voluntary migrants experience roughly 50% less acculturative stress than refugees, making this an important distinction. According to Schwartz (2010), there are four main categories of migrants: Voluntary immigrants: those that leave their country of origin to find employment, economic opportunity, advanced education, marriage, or to reunite with family members that have already immigrated. Refugees: those who have been involuntarily displaced by persecution, war, or natural disasters. Asylum seekers: those who willingly leave their native country to flee persecution or violence. Sojourners: those who relocate to a new country on a time-limited basis and for a specific purpose. It is important to note that this group fully intends to return to their native country. This type of entry distinction is important, but acculturative stress can also vary significantly within and between ethnic groups. Much of the scholarly work on this topic has focused on Asian and Latino/a immigrants, however, more research is needed on the effects of acculturative stress on other ethnic immigrant groups. Among U.S. Latinos, higher levels of adoption of the American host culture has been associated with negative effects on health behaviors and outcomes, such as increased risk for depression and discrimination, and increased risk for low self-esteem. However, some individuals also report "finding relief and protection in relationships" and "feeling worse and then feeling better about oneself with increased competencies" during the acculturative process. Again, these differences can be attributed to the age of the immigrant, the manner in which an immigrant exited their home country, and how the immigrant is received by both the original and host cultures. Recent research has compared the acculturative processes of documented Mexican-American immigrants and undocumented Mexican-American immigrants and found significant differences in their experiences and levels of acculturative stress. Both groups