While Americans, in general, are healthier today than they were 30 years ago, a large gap continues to exist between blacks and whites. The statistics are sobering:

*A black baby is twice as likely as a white baby to die before its first birthday.

*The life expectancy for a black person is 68 years, compared with 74 years for whites.

*Black women are about 2 1/2 times more likely to die from diabetes than white women.

*Black men are seven times more likely to be murdered than white men and have a greater chance of dying of cancer and heart disease.

*Some of the therapies used in treating patients are much less effective on blacks than whites.

*Doctors and health activists grappled with the reasons behind these facts at a recent two-day meeting of the Congressional Black Caucus Health Braintrust. Speakers offered several explanations for why blacks are more susceptible than whites to certain unhealthy conditions: Blacks are more likely than whites to be poor, to have unhealthy diets and to live and work in undesirable conditions -- which increases their stress level and limits their access to health care. Minorities are also more likely to live or work in places that expose them to carcinogens such as lead from car pollution or peeling paint.

Several speakers said the health gap between blacks and whites is widening and blamed it on funding cutbacks by the Reagan administration, including $2 billion from Aid to Families with Dependent Children (AFDC), and an 18 percent reduction in Maternal and Child Health funds. Others noted that many health resources have not reached those who needed help the most.

A major problem with current medical care, said psychiatrist Patricia A. Newton, of Baltimore's Provident Hospital, is that it focuses on "curing illness, not preventing it." For example, Newton said, funds have been poured into some communities to treat alcoholics and drug addicts, but not into studies and programs to address why certain minority groups are more susceptible to these conditions or how the trend can be reversed.

Newton urged programs to address the full range of health, which she defined as "physical, emotional, social, political, cultural and economic well-being."

Stress, depression, anger and low self-esteem are particular problems in the black community where unemployment rates are double that for whites, said Lawrence Gary, director of the Institute of Urban Affairs and Research at Howard University. Studies demonstrate, he said, that these factors often result in higher rates of smoking, alcoholism, drug abuse, child abuse and homicide. In addition, mental health specialists report that while suicide has always been more common among whites, blacks -- especially young men -- have in recent years been taking their own lives more often. The suicide rate among black men increased from four per 100,000 in 1960 to 11 per 100,000 in 1981 -- a jump of 171 percent.

Some of the reported increase in disease rates among blacks "may be more apparent than real," as a result of better data collection in minority communities, said Dr. M. Alfred Haynes, dean of the Charles Drew Postgraduate Medical School in Los Angeles. He stressed, however, that "poor people are sicker than rich people regardless of race . . . Poor people are more likely to accept a certain level of illness as natural," he said, and may wait until they are seriously ill before seeking medical care.

But Dr. Jack White, director of the Howard University Cancer Center called the "late for treatment" argument a "cop out." In all stages of cancer, he noted, blacks tend to have lower survival rates because they are often battling other major diseases. Especially if they are poor, he said, "they just don't have the proper resistance."

Lung cancer is the most prevalent form of that disease among black men, he said, followed by prostate tumors. Breast and colon/rectal malignancies are increasing in the black population, although more research is needed to determine why. Studies implicate hectic life style, alcohol consumption and cigarette smoking. However, preliminary data from a Howard University study suggests an increase in prostate cancer among men with better nutrition and a more affluent life style.

In treating many diseases, therapy must be based on racial differences in response to medications, noted Dr. Mark S. Johnson, acting chairman of the Family Practice Department at Meharry Medical School in Tennesee. An example: beta blocker drugs that work well for white patients with high blood pressure are not nearly as successful in blacks. Just 10 years ago researchers discovered, he said, that hypertensive blacks respond better to diuretics -- a group of drugs that work by reducing fluid retention, a condition particularly common among blacks.

Racial differences in response to treatment lead Johnson to advocate more studies geared specifically to blacks. "We cannot assume," he said, "that results from research using homogeneous samples can be generalized to the total population."

Several speakers addressed the most poignant example of programs and funds not reaching their target: the high infant mortality rate -- a statistic often used to measure the well-being of a particular group. Recent national figures show that 19 of every 1,000 black babies born in the U.S. die before their first birthday -- nearly twice the rate for whites. In the District of Columbia in 1983, there were 20.1 deaths per 1,000 live births among black babies, according to Alicia Fairley, an assistant to the city's health commissioner. The rate for whites: 8.6 per 1,000.

A large proportion of infant deaths among blacks, said Dr. Robert L. Johnson, a professor of pediatrics at the New Jersey School of Medicine, is a result of the high pregnancy rate among teen-agers who do not know how to care for themselves or their infants. Prenatal outreach programs for poor teenagers were working well in the late 1970s, he said, but cutbacks in the 1980s have meant more patients and fewer resources.

Consequently, Johnson said, "the pregnant 16-year-old needed (but could not get) more than a midwife visit. She needed someone to help her deal with the problems that led her to getting pregnant in the first place."