Since the first Thanksgiving almost 400 years ago, Americans have spent each fall counting our blessings for the abundance produced by this continent's food and agriculture system. It is a gift that has kept on giving: We Americans today are, in general, able to consume more food, with more variety and convenience, more suited to our individual tastes and costing a lower share of our incomes than ever before in human existence.

Even as we recognize this abundance, another long-held American tradition is continually working to improve on our present circumstances -- to keep pushing for innovative and better ways of doing things. That has certainly been so in agriculture, nutrition and health. In that spirit, people throughout our country will take part today in a number of activities organized around Food Day. We are proud to be honorary co-chairmen of this special and important day.

Food Day events and activities are designed to foster honest discussion, deeper knowledge and progress toward addressing critical topics in food, agriculture and nutrition -- spanning the food chain from farm families to family tables. Among Food Day's many laudable objectives are promoting improved nutrition and health, lessening hunger, increasing access to safe and healthy food, enhancing opportunities for farm families and rural communities in producing food, and conserving natural resources and protecting the environment.

Ever increasing scientific evidence shows that our typical modern diet includes too few fruits, vegetables and whole grains but a surplus of calories, highly processed foods, sweets, salt and saturated fats. We also know that better nutrition, and the improved health it brings, would prevent hundreds of thousands of premature deaths in the United States from heart disease, diabetes, stroke, cancer and other causes.

Food Day helps to focus attention on the practical steps that we all can take to enhance our nutrition and health. Changing dietary habits and tastes is not easy, even though the health benefits of doing so are obvious. Still, sound public policies can help promote and facilitate healthier food choices and better nutrition. For example, Americans of all income levels and geographic locations must have a variety of fresh, healthier food choices available. That's why we so strongly support policies that will help continue the growth of farmers markets, local food marketing, and farm-to-school sales. Besides better nutrition and health, these new marketing avenues also provide new income opportunities for family farms.

Food Day also reminds us that even here, in the world's richest nation, about one in seven households suffer food insecurity, meaning that the family's diet is impaired or limited in some way, with even higher rates in households with children. In the ongoing economic crisis, record numbers of Americans rely on the various federal nutrition assistance programs. It is thus astounding that, even in the face of such obvious need and hardship, some Americans are calling for slashing federal nutrition assistance.

A growing world population, seeking more affluent lifestyles and diets, is placing increasing demands on vital natural resources such as soil, water and wildlife. Food Day is also dedicated to encouraging and supporting farmers and ranchers who strengthen conservation and environmental practices on their land. Food Day will also focus much-needed attention on workers in food and agriculture occupations: the often hazardous nature of their jobs, difficult working conditions and generally low pay.

In short, Food Day is a great opportunity to recognize the many achievements and progress in America's food and agriculture system, while engaging in an honest and fair discussion about current issues and how they might be resolved. We urge all Americans to find a local Food Day event and join the dialogue.

Sen. Tom Harkin (D-Iowa) is chairman of the Health, Education, Labor and Pensions Committee and a senior member of the Appropriations and Agriculture committees. Rep. Rosa DeLauro (D-Conn.) is ranking member on the Appropriations Subcommittee on Labor, Health and Human Services, and Education.

This column first appeared on RollCall.com and is cross posted with author permission from Huffington Post.