The reproductive performances of livestock play an essential role in the economic management of the farm. The improvement of semen quantity and quality through the use of food supplements that lack substances which are forbidden in animal feeding, or that may have detrimental effects, is an important goal. Maca (Lepidium meyenii) is a plant that has been used for centuries in the Andes for nutrition and fertility enhancement in humans and animals. The aim of this study was to evaluate the effects of food supplementation of stallions with maca during the breeding season on spermatozoa parameters such as DNA fragmentation and shape, which are two predictive indexes of spermatozoa functionality. For this purpose, ejaculate volume, semen gel-free volume, sperm concentration and motility, total sperm count, sperm DNA fragmentation and sperm head parameters (length, width, perimeter, area, shape factor, roughness) were measured in four stallions. Maca food supplementation in stallions during breeding reduced the percentage of spermatozoa with fragmented DNA, increased significantly sperm concentration and exerted an elongation of the spermatozoa head, a condition that is believed to improve spermatozoa functionality, suggesting that food supplementation of maca could be useful in horse breeding during the breeding season.

Arginine (ARG) and its precursor citrulline (CIT) are popular dietary supplements, especially for the elderly. However, age-related reductions in lean body mass and alterations in organ functions could change their bioavailability. Pharmacokinetics and tolerance to amino acid (AA) loads are poorly documented in elderly subjects. The objective here was to characterise the plasma kinetics of CIT and ARG in a single-dosing study design. Eight fasting elderly men underwent two separate isomolar oral loading tests (10 g of CIT or 9·94 g of ARG). Blood was withdrawn over an 8-h period to measure plasma AA concentrations. Only CIT, ornithine and ARG plasma concentrations were changed. Volume of distribution was not dependent on AA administered. Conversely, parameters related to ARG kinetics were strongly dependent on AA administered: after ARG load, elimination was higher (ARG>CIT; P=0·041) and admission period+time at peak concentration was lower (ARG<CIT; P=0·033), and the combination of both phenomena results in a marked increase in ARG availability when CIT was administered (ARG<CIT; P=0·033) compared with ARG administration itself. In conclusion, a single CIT administration in the elderly is safe and well tolerated, and CIT proves to be a better in vivo ARG precursor than ARG itself in healthy elderly subjects.

The objective of the present study was to assess the impact of providing small-quantity lipid-based nutrient supplements (SQ-LNS) on the I status of young Burkinabe children. In total, thirty-four communities were assigned to intervention (IC) or non-intervention cohorts (NIC). IC children were randomly assigned to receive 20 g lipid-based nutrient supplements (LNS)/d containing 90 µg I with 0 or 10 mg Zn from 9 to 18 months of age, and NIC children received no SQ-LNS. All the children were exposed to iodised salt through the national salt iodization programme. Spot urinary iodine (UI), thyroid-stimulating hormone (TSH) and total thyroxine (T4) in dried blood spots as well as plasma thyroglobulin (Tg) concentrations were assessed at 9 and 18 months of age among 123 IC and fifty-six NIC children. At baseline and at 18 months, UI, TSH and T4 did not differ between cohorts. Tg concentration was higher in the NIC v. IC at baseline, but this difference did not persist at 18 months of age. In both cohorts combined, the geometric mean of UI was 339·2 (95 % CI 298·6, 385·2) µg/l, TSH 0·8 (95 % CI 0·7, 0·8) mU/l, T4 118 (95 % CI 114, 122) nmol/l and Tg 26·0 (95 % CI 24·3, 27·7) µg/l at 18 months of age. None of the children had elevated TSH at 18 months of age. Marginally more children in NIC (8·9 %) had low T4 (<65 nmol/l) compared with the IC (1·6 %) (P=0·052). Salt samples (n 106) were collected from randomly selected participants and assessed by titration for I content, which was on average 37 (sd 15) ppm (range 5–86 ppm); 95 % of households had adequately iodised salt (I>15 ppm). A reduction of SQ-LNS I content could be considered in settings with similarly successful salt iodisation programmes.

In 2000 an estimated £335×106 was spent on food supplements and herbal remedies in the UK. Until recently, The Trades Description Act 1968, the Food Safety Act 1990 and The Food Labelling Regulations 1996 (amended 2004) were the only form of regulation available to protect the public. The medical community has been concerned about the risk to patients of inaccurate dosages and poor-quality products as well as drug–nutrient and nutrient–nutrient interactions. Following growing concern about the type and quality of food supplements and herbal remedies available in the EU, the European Commission has published directives regulating food supplements (2002/46/EC) and herbal remedies (2004/24/EC and 2004/27/EC) available within the EU. The directives came into force in 2005 and limit the number and quality of permitted food supplements through the creation of a ‘positive list’ of approved supplements. In the present paper the new regulatory frameworks and the implications for the food supplement manufacturers, traditional and complementary therapists, the healthcare professions and patients will be examined. It would appear that there is considerable dissatisfaction with the regulations in their present form. Several questions remain: is regulation the answer; who decides which nutrients go on the positive list; what effect has the regulation had on patient safety and patient choice?