Eddie Singletary appeals the district court’s grant of summary judgment in favor of the Secretary of Health and Human Services affirming the denial of his application for disability benefits. We reverse.
Facts
Eddie Singletary is twenty-nine years old. He has completed the tenth grade and received his GED. He has also been in and out of several trade schools. For more than ten years, he has led a wandering, nomadic existence, travelling back and forth between Texas, Mississippi and Louisiana and living in hospitals, bus stations, missions, the woods and the homes of relatives. He has been sporadically employed, working for various intervals as a deckhand, roustabout, rigger, or galley-hand. He has also worked for short periods of timé at painting, plumbing, carpentry, air-conditioning, refrigeration, machine shops, loading and unloading trucks, and dish-washing. He has spent considerable amounts of time in various hospitals and mental institutions.
The doctors who have examined Singletary, and there have been many, have differed in their evaluations, diagnosing him at different times as suffering from schizophrenia, various psychoses, delusions, an antisocial personality, an inadequate personality, and a passive-aggressive personality. While they differ in their diagnoses, the doctors concluded that Singletary has serious, long-term mental impairments.
In 1982, Singletary applied for social security benefits, claiming that he was disabled due to his mental condition. His application was denied both initially and on reconsideration. In 1984, a hearing was conducted before an administrative law judge (AU), who recommended a finding of no disability. Singletary’s request for review was rejected by the Appeals Council, and the ALJ’s decision became the final decision of the Secretary of Health and Human Services. The district court, upon recommendation of a magistrate, determined that the Secretary’s determination was supported by substantial evidence, and granted summary judgment in favor of the Secretary.
Discussion
An individual is disabled under the Social Security Act only when he has a physical or mental impairment which has lasted or can be expected to last for at least 12 months and which is so severe that the claimant is unable to engage in substantial gainful employment. 42 U.S.C. § 423(d)(1)(A) (1982); 20 C.F.R. § 404.1505 (1985). Substantial gainful activity is work that involves significant and productive activities for pay or profit. Id. § 404.1510. To determine whether an impairment is so severe that it prevents a claimant from pursuing any gainful activity, the Secretary is required to engage in a five-step sequential evaluation process. Id. § 404.1520(b)-(f).
First, if the claimant is already employed, disability benefits are denied regardless of the severity of the impairment. Second, if the individual is not working, the Secretary must determine whether the claimed impairment is “severe.” See id. § 404.1521. If the impairment is severe, the Secretary must determine whether the impairment is so severe that the claimant is presumed to be unable to pursue any gainful activity. This determination is made by comparing the impairment to a specific Listing of Impairments. See id. § 404, Subpart P, Appendix 1. If the claimant’s impairment does not fall within the Listing of Impairments, the Secretary must determine whether the individual has a sufficient “residual functional capacity” to perform the kind of work he did in the past. See id. § 404.1545. Fifth, if the individual is unable to do past relevant work, then the Secretary must determine, based on the individual’s age, education, work experience and residual functional capacity, whether the claimant can perform any other work which exists in the national economy. See id. § 404.1566.
Determining whether a claimant is disabled because of a mental condition under the above sequential process can be a difficult task. In some cases, the mental im*821pairment may be so severe that the claimant is presumed to be incapable of working. See, e.g., Moore v. Secretary of the United States Dept. of Health and Human Services, 778 F.2d 127 (2d Cir.1985) (finding that the claimant was disabled under the Listing of Impairments). Quite often, however, the claimant is capable of finding a job and working for short periods of time. The nature of the mental impairment is such, however, that the claimant is unable to remain employed for any significant period of time. Such circumstances raise two important questions. First, does the impairment meet the 12 month duration requirement? Second, is the impairment so severe as to prevent the claimant from engaging in substantial gainful activity? These questions are to a certain extent intertwined, and this has caused some confusion, confusion which was evident in this case.
I. The Durational Requirement
The AU concluded that Singletary’s mental condition “does not appear to have been severe enough to have prevented substantial gainful employment for more than short periods of time — far less than twelve continuous months.” This finding evidences a misunderstanding of the duration requirement. It confuses the duration requirement, which applies only to the impairment, with the severity requirement, which determines whether the impairment prevents the claimant from working.
The Social Security Act defines “disability” as the
inability to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment which can be expected to result in death or which has lasted or can be expected to last for a continuous period of not less than 12 months.
42 U.S.C. § 423(d)(1)(A) (1982). The statute quite clearly requires that it is the impairment only which must last for a continuous period. Normally, of course, when a claimant has an impairment severe enough to prevent him from working, he will be unable to work for as long as the impairment lasts. This is particularly true when the impairment is physical. The statute, however, does not require that a claimant be unable to engage in work during the entire 12 month period. See also 20 C.F.R. §§ 404.1505(a); 404.1509; 404.1510. The ability of a claimant to engage in work for limited periods of time certainly calls into question the severity of the impairment, but it does not necessarily determine whether the impairment, however severe, has lasted for at least 12 months.
While a claimant need only show that an alleged impairment has lasted or can be expected to last for the 12 month period to meet the duration requirement, a claimant alleging a mental impairment may face a difficulty not presented in cases involving physical impairment. As one court has stated,
While the mere existence of symptom-free periods may negate a finding of disability when a physical impairment is alleged, symptom-free intervals do not necessarily compel such a finding when a mental disorder is the basis of the claim. Unlike a physical impairment, it is extremely difficult to predict the course of mental illness. Symptom-free intervals, though sometimes indicative of a remission in the mental disorder, are generally of uncertain duration and marked by an impending possibility of relapse. Realistically, a person with a mental, impairment may be unable to engage in competitive employment, as his ability to work may be sporadically interrupted by unforeseeable mental setbacks.
Lebus v. Harris, 526 F.Supp. 56, 61 (N.D.Cal. 1981).
Because of such considerations, the courts which have considered the question have concluded that a claimant whose claim is based on a mental condition does not have to show a 12 month period of impairment unmarred by any symptom-free interval. See, e.g., Miller v. Heckler, 747 F.2d 475, 478 (8th Cir.1984); Dreste v. Heckler, 741 F.2d 224, 226 n. 2 (8th Cir.1984). We agree with the assessment of these courts. *822A finding that a claimant has a. mental impairment which manifests itself from time to time over a long-term period is not inconsistent with the language of the statute, which requires that an impairment last “for a continuous period of 12 months.” 42 U.S.C. § 423(d)(1)(A) (1982); see also 20 C.F.R. § 404.1509. Of course, as required by the regulations, a claimant must present medical evidence which indicates that his mental condition is a long-term problem and not just a temporary set-back. See 20 C.F.R. § 404.1508.
In this case, there is no question but that Singletary presented such evidence. With years of visits to hospitals and numerous diagnoses of mental problems, Singletary’s impairment unquestionably lasted for more than 12 months. Moreover, the doctors who saw Singletary all determined that his problems involved long-term difficulties. There can be no doubt, therefore, that Singletary met the duration requirement.
II. Substantial Gainful Activity
The AU determined that Singletary was suffering from a personality disorder. The AU also concluded, however, that Singletary was able to engage in substantial gainful activity because he was capable of performing work, such as dishwashing, which he had done in the past. In reaching this conclusion, the AU ignored one very important aspect of Singletary’s mental condition: the extent to which his condition prevented him from maintaining regular employment.
A finding that a claimant is able to engage in substantial gainful activity requires more than a simple determination that the claimant can find employment and that he can physically perform certain jobs; it also requires a determination that the claimant can hold whatever job he finds for a significant period of time. See Parsons v. Heckler, 739 F.2d 1334, 1340 (8th Cir. 1984) (“the ability of a claimant to perform jobs in the national economy must take into account the actual ability of the claimant to find and hold a job in the real world”) (emphasis added); Tennant v. Schweiker, 682 F.2d 707, 709-10 (8th Cir.1982) (where individual bases his claim on a personality disorder, “the dispute focuses on whether the claimant has the emotional capacity to engage in sustained employment”). A determination that a claimant is unable to continue working for significant periods of time must, however, be supported by more than a claimant’s personal history; it must also be supported by medical evidence. See 20 C.F.R. §§ 404.1546; 404.1560.
There was substantial evidence to support Singletary’s claim that he was unable to hold a job. His personal history indicated that he was never able to hold a job for long periods of time. He testified that even his relatives would not employ him as they claimed that he did more harm than good. As indicated earlier, all the doctors who examined Singletary had determined that he suffered from various mental disorders. In their reports, they discussed his poor judgment, his inability to relate socially, his antisocial tendencies, and his poor insight. Dr. Thomas Roach, of the Southeast Louisiana Hospital, determined in 1978 that Singletary’s prognosis was “poor ... he will no doubt be back.” Another doctor concluded that Singletary was an antisocial personality who “was not as successful as most because he had less intellectual endowment.” Most recently, in 1984, Dr. Louis Provenza stated that “[d]ue to his diagnosis of a schizoid type personality disorder, it is doubtful that the patient may be able to return to employment.”
Despite the substantial, indeed overwhelming, evidence in support of Singletary’s claim, the AU based his conclusion that Singletary could engage in substantial gainful activity on determinations by some of the doctors that Singletary was “employable.” Of course, conflicts in the evidence, including those arising in medical opinions, are to be resolved by the Secretary, Laffoon v. Califano, 558 F.2d 253, 254-55 (5th Cir.1977), and we must uphold the Secretary’s determination if it is supported by substantial evidence. But the *823substantial evidence test does not involve a simple search of the record for isolated bits of evidence which support the Secretary’s decision. We must consider the record as a whole, Orlando v. Heckler, 776 F.2d 209, 213 (7th Cir.1985), and “ ‘[t]he substantiality of evidence must take into account whatever in the record fairly detracts from its weight,’ ” Parsons, 739 F.2d at 1339 (quoting Universal Camera Corp. v. NLRB, 340 U.S. 474, 488, 71 S.Ct. 456, 464, 95 L.Ed. 456 (1951)).
We think that when the record as a whole is considered the conflict between the medical opinions over whether Singletary is “employable” is more apparent than real. Dr. Boudreaux examined Singletary numerous times from 1977 to 1983 while Singletary was at the Mississippi VA Hospital. In his last report, written in September 1983, Dr. Boudreaux concluded that Singletary is “an inadequate personality with periodic alcohol and drug abuse that leads to transient psychotic episodes in a person with low average intelligence, who has had some diffuse brain damage, has had a nomadic life and who had a chaotic rearing.” He listed Singletary as “employable,” but he also stated that Singletary is a “very inept person who will probably always have vocational, social and interpersonal problems ” (emphasis added). Similarly, in a report written in October 1982, Dr. Frank Covington concluded that Singletary could engage in gainful employment “at the present time.” Dr. Covington also stated, however, that Singletary’s judgment was impaired, his insight into his problems was poor, his ability to relate to others was impaired, and he suffered from “moderate restriction of daily activities, moderate deterioration in personal habits, and moderate constriction of interests.” According to Dr. Covington, Singletary’s prognosis was “guarded.”
These reports clearly indicate a determination by both doctors that Singletary could find and physically perform certain jobs. Such a finding is also supported by his personal history. But it is at least questionable whether these reports would support a finding that Singletary could remain employed for significant periods of time. Indeed, Dr. Boudreaux’s conclusion that Singletary would always have vocational problems and Dr. Covington’s conclusion that Singletary could maintain employment at the present time may contradict such a finding. The concern which these doctors expressed over Singletary’s ability to remain employed indicates that their opinions of his “employability” were not in conflict with Singletary’s other medical records or his personal history.
When viewed as a whole, Singletary’s history presents the picture of an individual living a tragic, chaotic personal life who has been unable to remain employed for more than limited periods of time. He has been hospitalized repeatedly over a long period of time for psychiatric problems, and the record is replete with discussions of his inappropriate behavior and poor social adjustment. Based on such a record, we are not satisfied that substantial evidence supports a determination that Singletary could obtain and maintain employment, or that this was the finding of the ALJ.
We reverse the judgment of the district court affirming the decision of the Secretary. We remand to the district court with instructions to remand the case to the Secretary for reconsideration in accord with this opinion.
REVERSED and REMANDED.