Articles
Culinary Herbs: Providing More Than Just Colour And Flavour
This article by Winston J. Craig (Ph.D., MPH, RD), also published in Sanitarium’s Newsletter “Good Food News” Vol 14, no.4, 2002, has been reproduced on this website with the permission of Sanitarium.
Winston is Professor of Nutrition in the Department of Nutrition at Andrews University, Michigan, USA and has a specific interest in the use and safety of herbs and spices.
Herbs and spices have been grown and used for thousands of years to preserve and flavour foods. The ability of herbs and spices to delay food spoilage is due in large part to their rich content of antioxidants (substances which help to protect against damage that can be caused by compounds called free radicals). The unique flavours associated with different herbs are provided by the aromatic properties of their essential oils and oleoresins (natural plant substances). The actual strength of their flavours or “pungency” is due to the herbs’ alkaloid (organic compound) content. In addition, some herbs such as paprika and turmeric add red and yellow colours to food.
Cooking with Herbs
With the current emphasis on eating more healthful diets that are low in fat and salt, it is a good idea to think about using various herbs and spices to flavour your food.
Due to the influence of multiculturalism in Australia and New Zealand over recent decades, we have been exposed to a variety of cooking methods and uniquely flavoured ethnic dishes. The popularity of Italian, Greek, Chinese, Indian, Thai, and other ethnic cuisines has lead to the availability of a large range of herbal seasonings. For example:
- Oregano is essential in the preparation of Italian and Spanish food and is commonly used to flavour pizza;
- Chilli pepper is commonly used in many Italian and Indian dishes;
- Italians use sweet basil for flavouring legumes and in many of their tomato dishes;
- Thyme has a prominent place in French cuisine;
- Rosemary is a common ingredient in Italian and French dishes;
- Cinnamon, cloves, cumin, ginger, and turmeric are common ingredients in Indian dishes; and
- Lemon grass, coriander, and ginger add unique flavours to Thai and other Asian cuisine.
Garlic
For centuries garlic has been used in Greek, Italian, Indian, and Asian dishes. Garlic can be used in a variety of dips, vegetable dishes, soups, and some baked goods. Likewise, onions or dehydrated onion can be used to enhance the flavour of most vegetables, salads, soups, gravies, and many dishes.
Fresh vs Dried Herbs – Which is better?
Freshly picked herbs add rich and vigorous flavours to food. Dried herbs usually smell and taste somewhat differently from their fresh counterparts. During the herb drying process, there is usually a loss in the fragrant oils from the fresh herbs, leaving some of the more bitter flavours behind. Furthermore, the flavour of most dried herbs tends to diminish with time so any bottles containing dried herbs that are older than 12 months should probably be discarded. So, for a flavoursome meal, try to use either fresh herbs or “fresh” dried herbs.
Herbs and Heart Health
There are a few herbs such as ginger, garlic and onions that may provide some help for people with hyperlipidemia (high blood cholesterol/triglyceride levels), or an abnormal tendency to form blood clots. Ginger contains a number of terpenoid and phenolic compounds (natural plant compounds) that inhibit the formation of blood clots(1). Ginger adds a nice spicy flavour to stir-fried vegetables, fruit salad and homemade biscuits.
Garlic has been used medicinally for many centuries. The compound producing much of the activity of garlic is allicin, which is released when the intact cells of a garlic clove are cut or crushed. Allicin inhibits the growth of a number of bacteria, moulds, yeasts (including Candida), and viruses(2). The regular use of garlic can also be useful in lowering the risk of heart attacks and strokes since it lowers both total and LDL (‘bad’) cholesterol levels and triglyceride levels, without affecting HDL (‘good’) cholesterol levels. Research suggests that on average, consuming half to one clove of garlic per day for three to six months can reduce elevated blood cholesterol levels by about 10%(3). Garlic also possesses anti-clotting activity and prevents blood platelets from sticking together due in part to the presence of sulphur compounds produced from the breakdown of allicin(4).
The odour-modified garlic extract (ie. Kyolic) has been found to be just as effective as fresh garlic for lowering blood cholesterol levels(5). The use of enteric-coated garlic pills (the coating on the pills allows the ingredients to pass through the stomach unchanged and into the intestines) are another way to cut down on odour problems while still enjoying the benefits of garlic. Data also suggests that garlic may be useful for people with mild hypertension (high blood pressure)(6).
Onions contain many compounds that are identical or similar to those found in garlic. However, garlic is considered a more potent herb since it contains about three times the level of sulphur compounds found in onions. Onions are also considered anti-clotting agents. A whole family of sulphur compounds, known as alpha-sulfinyl disulfides, isolated from onions have been shown to strongly prevent blood platelets from sticking together(7). It is important to note that unlike garlic, eating onions has not been shown to lower blood lipid levels.
Fenugreek is a herb that is commonly used in Indian recipes. The rich content of saponins (natural plant compounds) and the soluble fibre in fenugreek is useful in lowering blood cholesterol levels. In addition, the terpenoids (compounds present in essential oils), found in lemon grass, and the herbs belonging to the genus Lamiaceae (mint family) can help to block the production of cholesterol(8).
Onions, rosemary, sage, thyme, and other herbs contain significant amounts of flavonoids (natural plant compounds). The flavonoid content of a herb can vary from plant to plant based upon where the herb was grown, the maturity of the plant when harvested, the plant variety, and the part of the herb used. Flavonoids can act as antioxidants to protect ‘LDL’ cholesterol from being oxidised (oxidised ‘LDL’ cholesterol is the type of cholesterol that clogs arteries). They can also inhibit the formation of blood clots and provide anti-inflammatory and anti-tumour activity. Studies indicate that a higher intake of flavonoids is linked to a lower incidence of heart disease and stroke(9).
SUMMARY TABLE
Functions of Commonly Used Health-Promoting Herbs and Spices
Physiological Function | Herb With Desired Function |
Lowers total and LDL cholesterol levels | garlic linseed fenugreek lemon grass |
Inhibits blood clots | garlic onions linseed ginger |
Improves blood glucose control or insulin activity | fenugreek linseed/flaxseed cinnamon |
Cancer-protective properties | garlic, onions, chives, leeks Lamiaceae herbs (mint family) Umbelliferous herbs (parsley family) linseed ginger tumeric |
Herbs and Managing Diabetes
Diabetes is a disease characterised by elevated blood glucose (sugar) levels. The unregulated blood glucose levels may result from either a lack of insulin (ie. Type 1 diabetes or insulin-dependant diabetes) or a reduction in its effectiveness (ie. Type 2 diabetes or non insulin-dependant diabetes). Careful dietary habits and regular exercise are essential components in the management of diabetes, especially Type 2 diabetes. In addition, there are a few herbs and spices that may help to lower blood glucose levels and so may be a useful added therapy in the management of diabetes.
The consumption of fenugreek seeds, containing high levels of soluble fibre, can help to lower blood glucose levels in people with diabetes. Research in India found that glucose tolerance improved, urinary glucose excretion decreased by 70%, and insulin responses were reduced in people with diabetes after fenugreek was used for 10 days. Total serum cholesterol, ‘LDL’ cholesterol and triglyceride levels, but not ‘HDL’ cholesterol, all significantly decreased by about 20% when fenugreek was added to the diet(10). These changes in blood lipids are important factors for a person with Type 2 diabetes as they can tend to have elevated blood lipids.
Linseed/flaxseed, cinnamon, and some herbs may also provide benefits to people with diabetes. Subjects consuming bread containing 25% linseed meal showed an almost 30% improvement in a glucose tolerance test compared with those who ate plain bread(11). An extract from cinnamon has been found to enhance insulin activity(12). It has been suggested that cinnamon may be useful for people with Type 2 diabetes.
Preliminary studies have also reported improved glucose tolerance or anti-diabetic activity through the use of other herbs including garlic, onions, bay leaves, cloves, cumin, and turmeric(13). Further research is needed to confirm all these findings and to discover whether there is any clinical significance to the blood glucose lowering effects of these herbs.
Herbs and Cancer Prevention
A number of commonly used herbs have been identified as possessing cancer-protective properties. These include members of the:
- Allium family ie. garlic, onions, chives, leeks;
- Lamiaceae family ie. basil, mint, oregano, peppermint, rosemary, sage, thyme;
- Zingiberaceae family ie. turmeric, ginger; and
- Umbelliferae (parsley) family ie. anise, caraway, celery, chervil, coriander, cumin, dill, fennel, and parsley.
Garlic has been shown to especially reduce the development of stomach, and colon cancer. A study of more than 41,000 women followed for five years in the United States revealed that risk of colon cancer was 32% lower in people with the highest garlic consumption compared to those with the lowest consumption(14). The rich content of sulfides, disulfides and trisulfides in garlic is thought to provide its cancer preventive properties. Also, a Dutch study revealed that stomach cancer for those consuming the highest level of onions (at least half an onion a day) was about 50% lower than that in people consuming no onions(15).
Turmeric and ginger have also been suggested to inhibit cancer growth. Both of these herbs contain natural compounds called curcuminoids, which are thought to inhibit cancer development.
Final Wrap-Up
A variety of commonly used culinary herbs have the potential for use in the treatment of elevated blood lipids and blood glucose, while some may provide protection against cancer. In most cases further research is needed to confirm the health benefits of herbs. In the meantime, why not try experimenting with herbs (preferably fresh herbs) in your cooking – they will definitely add to the flavour, colour and aroma of your dishes and at the same time will probably be helping you to stay well!
References:
- Kawakishi S, Morimitsu Y, Osawa T, Chemistry of ginger components and inhibitory factors of the arachidonic acid cascade, in Food Phytochemicals for Cancer Prevention II. Teas, Spices and Herbs , Huang MT, Osawa T, Ho CT, Rosen RT, eds., American Chemical Society, Washington DC, 1994, 244.
- Koch HP, Lawson LD (editors). Garlic. The Science and Therapeutic Application of Allium sativum L. and Related Species . Second edition. Williams & Wilkins, Baltimore, MD,1996.
- Warshafsky S, Kramer RS, Sivak SL. Effect of garlic on total serum cholesterol: a meta-analysis. Ann Intern Med 1993; 119:599-605.
- Kleijnen J, Knipschild P, ter Riet GT. Garlic, onions and cardiovascular risk factors. A review of the evidence from human experiments with emphasis on commercially available preparations. Br J Clin Pharmacol 1989; 28:535-544.
- Yeh YY, Liu L. Cholesterol-lowering effect of garlic extracts and organosulfur compounds: human and animal studies. J. Nutr. 2001; 131: 989S-993S.
- Silagy CA, Neil HA. A meta-analysis of the effect of garlic on blood pressure. J Hypertens 1994; 12:463-468.
- Kawakishi S, Morimitsu Y. Sulfur chemistry of onions and inhibitory factors of the arachidonic acid cascade, In: Huang MT, Osawa T, Ho CT, Rosen RT, eds. Food Phytochemicals for Cancer Prevention I. Fruits and Vegetables. Washington DC: American Chemical Society,1994; 120-127.
- Case GL, He L, Mo H, Elson CE. Induction of geranyl pyrophosphate pyrophosphatase activity by cholesterol-suppressive isoprenoids. Lipids 1995; 30:357-359.
- Knekt P, Kumpulainen J, Jarvinen R, Rissanen H, Heliovaara M, Reunanen A, Hakulinen T, Aromaa A. Flavonoid intake and risk of chronic diseases. Am J Clin Nutr 2002;76:560-8.
- Sharma RD, Raghuram TC. Hypoglycaemic effect of fenugreek seeds in non-insulin dependant diabetic subjects. Nutr Res 1990; 10:731-739.
- Cunnane SC, Ganguli S, Menard C, Liede AC, Hamadeh MJ, Chen ZY, Wolever TM, Jenkins DJ. High alpha-linolenic acid flaxseed (Linum usitatissimum ): some nutritional properties in humans. Br J Nutr 1993; 69:443-453.
- Imparl-Radosevich J, Deas S, Polansky MM, Baedke DA, Ingebritsen TS, Anderson RA, Graves DJ. Regulation of PTP-1 and insulin receptor kinase by fractions from cinnamon: implications for cinnamon regulation of insulin signalling. Horm Res 1998; 50:177-182.
- Broadhurst CL, Polansky MM, Anderson RA. Insulin-like biological activity of culinary and medicinal plant aqueous extracts in vitro. J Agric Food Chem 2000;48(3):849-852.
- Steinmetz KA, Kushi LH, Bostick RM, Folsom AR, Potter JD. Vegetable, fruit, and colon cancer in the Iowa women’s health study. Am J Epidemiol 1994; 139:1-15.
- Dorant E, van den Brandt PA, Goldbohm RA, Sturmans F. Consumption of onions and a reduced risk of stomach carcinoma. Gastroenterology 1996; 110:12-20.
Added to site on : Monday, 31 March 2003